Nanomaterials

15 pages, 3708 KiB

Open AccessEditor’s ChoiceArticle

Construction of 2D/2D Mesoporous WO₃/CeO₂ Laminated Heterojunctions for Optimized Photocatalytic Performance

by Wenjie Wang, Decai Yang, Yifan Mou, Lijun Liao, Shijie Wang, Liping Guo, Xuepeng Wang, Zhenzi Li and Wei Zhou

Nanomaterials 2023, 13(11), 1798; https://doi.org/10.3390/nano13111798 - 4 Jun 2023

Cited by 3 | Viewed by 1702

Abstract

Photocatalytic elimination of antibiotics from the environment and drinking water is of great significance for human health. However, the efficiency of photoremoval of antibiotics such as tetracycline is severely limited by the prompt recombination of electron holes and slow charge migration efficacy. Fabrication [...] Read more.

Photocatalytic elimination of antibiotics from the environment and drinking water is of great significance for human health. However, the efficiency of photoremoval of antibiotics such as tetracycline is severely limited by the prompt recombination of electron holes and slow charge migration efficacy. Fabrication of low-dimensional heterojunction composites is an efficient method for shortening charge carrier migration distance and enhancing charge transfer efficiency. Herein, 2D/2D mesoporous WO₃/CeO₂ laminated Z-scheme heterojunctions were successfully prepared using a two-step hydrothermal process. The mesoporous structure of the composites was proved by nitrogen sorption isotherms, in which sorption-desorption hysteresis was observed. The intimate contact and charge transfer mechanism between WO₃ nanoplates and CeO₂ nanosheets was investigated using high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy measurements, respectively. Photocatalytic tetracycline degradation efficiency was noticeably promoted by the formation of 2D/2D laminated heterojunctions. The improved photocatalytic activity could be attributed to the formation of Z-scheme laminated heterostructure and 2D morphology favoring spatial charge separation, confirmed by various characterizations. The optimized 5WO₃/CeO₂ (5 wt.% WO₃) composites can degrade more than 99% of tetracycline in 80 min, achieving a peak TC photodegradation efficiency of 0.0482 min⁻¹, which is approximately 3.4 times that of pristine CeO₂. A Z-scheme mechanism is proposed for photocatalytic tetracycline by from WO₃/CeO₂ Z-scheme laminated heterojunctions based on the experimental results. Full article

(This article belongs to the Special Issue Applications of Nanomaterials for Electrocatalysis, Photocatalysis, Photoelectrochemical Solar Cells and Toxicity)

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26 pages, 8534 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Size Matters? A Comprehensive In Vitro Study of the Impact of Particle Size on the Toxicity of ZnO

by Montserrat Mitjans, Laura Marics, Marc Bilbao, Adriana S. Maddaleno, Juan José Piñero and M. Pilar Vinardell

Nanomaterials 2023, 13(11), 1800; https://doi.org/10.3390/nano13111800 - 4 Jun 2023

Cited by 4 | Viewed by 1848

Abstract

This study describes a comparative in vitro study of the toxicity behavior of zinc oxide (ZnO) nanoparticles and micro-sized particles. The study aimed to understand the impact of particle size on ZnO toxicity by characterizing the particles in different media, including cell culture [...] Read more.

This study describes a comparative in vitro study of the toxicity behavior of zinc oxide (ZnO) nanoparticles and micro-sized particles. The study aimed to understand the impact of particle size on ZnO toxicity by characterizing the particles in different media, including cell culture media, human plasma, and protein solutions (bovine serum albumin and fibrinogen). The particles and their interactions with proteins were characterized in the study using a variety of methods, including atomic force microscopy (AFM), transmission electron microscopy (TEM), and dynamic light scattering (DLS). Hemolytic activity, coagulation time, and cell viability assays were used to assess ZnO toxicity. The results highlight the complex interactions between ZnO NPs and biological systems, including their aggregation behavior, hemolytic activity, protein corona formation, coagulation effects, and cytotoxicity. Additionally, the study indicates that ZnO nanoparticles are not more toxic than micro-sized particles, and the 50 nm particle results were, in general, the least toxic. Furthermore, the study found that, at low concentrations, no acute toxicity was observed. Overall, this study provides important insights into the toxicity behavior of ZnO particles and highlights that no direct relationship between nanometer size and toxicity can be directly attributed. Full article

(This article belongs to the Special Issue Toxicity and Ecotoxicity Assessment of Nanomaterials by In Vitro and In Vivo Models)

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22 pages, 7173 KiB

Open AccessEditor’s ChoiceArticle

Comparative Study of the U(VI) Adsorption by Hybrid Silica-Hyperbranched Poly(ethylene imine) Nanoparticles and Xerogels

by Michael Arkas, Konstantinos Giannakopoulos, Evangelos P. Favvas, Sergios Papageorgiou, George V. Theodorakopoulos, Artemis Giannoulatou, Michail Vardavoulias, Dimitrios A. Giannakoudakis, Konstantinos S. Triantafyllidis, Efthalia Georgiou and Ioannis Pashalidis

Nanomaterials 2023, 13(11), 1794; https://doi.org/10.3390/nano13111794 - 2 Jun 2023

Cited by 5 | Viewed by 1785

Abstract

Two different silica conformations (xerogels and nanoparticles), both formed by the mediation of dendritic poly (ethylene imine), were tested at low pHs for problematic uranyl cation sorption. The effect of crucial factors, i.e., temperature, electrostatic forces, adsorbent composition, accessibility of the pollutant to [...] Read more.

Two different silica conformations (xerogels and nanoparticles), both formed by the mediation of dendritic poly (ethylene imine), were tested at low pHs for problematic uranyl cation sorption. The effect of crucial factors, i.e., temperature, electrostatic forces, adsorbent composition, accessibility of the pollutant to the dendritic cavities, and MW of the organic matrix, was investigated to determine the optimum formulation for water purification under these conditions. This was attained with the aid of UV-visible and FTIR spectroscopy, dynamic light scattering (DLS), ζ-potential, liquid nitrogen (LN₂) porosimetry, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Results highlighted that both adsorbents have extraordinary sorption capacities. Xerogels are cost-effective since they approximate the performance of nanoparticles with much less organic content. Both adsorbents could be used in the form of dispersions. The xerogels, though, are more practicable materials since they may penetrate the pores of a metal or ceramic solid substrate in the form of a precursor gel-forming solution, producing composite purification devices. Full article

(This article belongs to the Special Issue Nanoscale Materials for Water Purification and Catalysis)

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15 pages, 3945 KiB

Open AccessEditor’s ChoiceArticle

Calculation of Self, Corrected, and Transport Diffusivities of Isopropyl Alcohol in UiO-66

by Chinmay V. Mhatre, Jacob J. Wardzala, Priyanka B. Shukla, Mayank Agrawal and J. Karl Johnson

Nanomaterials 2023, 13(11), 1793; https://doi.org/10.3390/nano13111793 - 2 Jun 2023

Cited by 4 | Viewed by 2111

Abstract

The UiO-6x family of metal-organic frameworks has been extensively studied for applications in chemical warfare agent (CWA) capture and destruction. An understanding of intrinsic transport phenomena, such as diffusion, is key to understanding experimental results and designing effective materials for CWA capture. However, [...] Read more.

The UiO-6x family of metal-organic frameworks has been extensively studied for applications in chemical warfare agent (CWA) capture and destruction. An understanding of intrinsic transport phenomena, such as diffusion, is key to understanding experimental results and designing effective materials for CWA capture. However, the relatively large size of CWAs and their simulants makes diffusion in the small-pored pristine UiO-66 very slow and hence impractical to study directly with direct molecular simulations because of the time scales required. We used isopropanol (IPA) as a surrogate for CWAs to investigate the fundamental diffusion mechanisms of a polar molecule within pristine UiO-66. IPA can form hydrogen bonds with the

μ_{3}

-OH groups bound to the metal oxide clusters in UiO-66, similar to some CWAs, and can be studied by direct molecular dynamics simulations. We report self, corrected, and transport diffusivities of IPA in pristine UiO-66 as a function of loading. Our calculations highlight the importance of the accurate modeling of the hydrogen bonding interactions on diffusivities, with about an order of magnitude decrease in diffusion coefficients when the hydrogen bonding between IPA and the

μ_{3}

-OH groups is included. We found that a fraction of the IPA molecules have very low mobility during the course of a simulation, while a small fraction are highly mobile, exhibiting mean square displacements far greater than the ensemble average. Full article

(This article belongs to the Topic Metal Organic Frameworks and Derived Materials for Advanced Applications)

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15 pages, 6194 KiB

Open AccessEditor’s ChoiceArticle

Zinc Oxide Nanoparticles—Solution-Based Synthesis and Characterizations

by Khagendra P. Bhandari, Dhurba R. Sapkota, Manoj K. Jamarkattel, Quenton Stillion and Robert W. Collins

Nanomaterials 2023, 13(11), 1795; https://doi.org/10.3390/nano13111795 - 2 Jun 2023

Cited by 13 | Viewed by 4295

Abstract

Zinc oxide (ZnO) nanoparticles have shown great potential because of their versatile and promising applications in different fields, including solar cells. Various methods of synthesizing ZnO materials have been reported. In this work, controlled synthesis of ZnO nanoparticles was achieved via a simple, [...] Read more.

Zinc oxide (ZnO) nanoparticles have shown great potential because of their versatile and promising applications in different fields, including solar cells. Various methods of synthesizing ZnO materials have been reported. In this work, controlled synthesis of ZnO nanoparticles was achieved via a simple, cost-effective, and facile synthetic method. Using transmittance spectra and film thickness of ZnO, the optical band gap energies were calculated. For as-synthesized and annealed ZnO films, the bandgap energies were found to be 3.40 eV and 3.30 eV, respectively. The nature of the optical transition indicates that the material is a direct bandgap semiconductor. Spectroscopic ellipsometry (SE) analysis was used to extract dielectric functions where the onset of optical absorption of ZnO was observed at lower photon energy due to annealing of the nanoparticle film. Similarly, X-ray diffraction (XRD) and scanning electron microscopy (SEM) data revealed that the material is pure and crystalline in nature, with the average crystallite size of ~9 nm. Full article

(This article belongs to the Topic Nanomaterials for Energy and Environmental Applications)

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29 pages, 7227 KiB

Open AccessEditor’s ChoiceReview

A Review of the Relationship between Gel Polymer Electrolytes and Solid Electrolyte Interfaces in Lithium Metal Batteries

by Xiaoqi Yu, Zipeng Jiang, Renlu Yuan and Huaihe Song

Nanomaterials 2023, 13(11), 1789; https://doi.org/10.3390/nano13111789 - 1 Jun 2023

Cited by 8 | Viewed by 3516

Abstract

Lithium metal batteries (LMBs) are a dazzling star in electrochemical energy storage thanks to their high energy density and low redox potential. However, LMBs have a deadly lithium dendrite problem. Among the various methods for inhibiting lithium dendrites, gel polymer electrolytes (GPEs) possess [...] Read more.

Lithium metal batteries (LMBs) are a dazzling star in electrochemical energy storage thanks to their high energy density and low redox potential. However, LMBs have a deadly lithium dendrite problem. Among the various methods for inhibiting lithium dendrites, gel polymer electrolytes (GPEs) possess the advantages of good interfacial compatibility, similar ionic conductivity to liquid electrolytes, and better interfacial tension. In recent years, there have been many reviews of GPEs, but few papers discussed the relationship between GPEs and solid electrolyte interfaces (SEIs). In this review, the mechanisms and advantages of GPEs in inhibiting lithium dendrites are first reviewed. Then, the relationship between GPEs and SEIs is examined. In addition, the effects of GPE preparation methods, plasticizer selections, polymer substrates, and additives on the SEI layer are summarized. Finally, the challenges of using GPEs and SEIs in dendrite suppression are listed and a perspective on GPEs and SEIs is considered. Full article

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12 pages, 5167 KiB

Open AccessEditor’s ChoiceArticle

Enhanced Photoluminescence and Random Lasing Emission in TiO₂-Decorated FAPbBr₃ Thin Films

by Xiaohong Liu, Caixia Xu and Hongquan Zhao

Nanomaterials 2023, 13(11), 1761; https://doi.org/10.3390/nano13111761 - 30 May 2023

Cited by 1 | Viewed by 1771

Abstract

Herein, titanium-dioxide-decorated organic formamidinium lead bromide perovskite thin films grown by the one-step spin-coating method are studied. TiO₂ nanoparticles are widespread in FAPbBr₃ thin films, which changes the optical properties of the perovskite thin films effectively. Obvious reductions in the absorption [...] Read more.

Herein, titanium-dioxide-decorated organic formamidinium lead bromide perovskite thin films grown by the one-step spin-coating method are studied. TiO₂ nanoparticles are widespread in FAPbBr₃ thin films, which changes the optical properties of the perovskite thin films effectively. Obvious reductions in the absorption and enhancements in the intensity of the photoluminescence spectra are observed. Over 6 nm, a blueshift of the photoluminescence emission peaks is observed due to 5.0 mg/mL TiO₂ nanoparticle decoration in the thin films, which originates from the variation in the grain sizes of the perovskite thin films. Light intensity redistributions in perovskite thin films are measured by using a home-built confocal microscope, and the multiple scattering and weak localization of light are analyzed based on the scattering center of TiO₂ nanoparticle clusters. Furthermore, random lasing emission with sharp emission peaks is achieved in the scattering perovskite thin films with a full width at the half maximum of 2.1 nm. The multiple scattering of light, the random reflection and reabsorption of light, and the coherent interaction of light within the TiO₂ nanoparticle clusters play important roles in random lasing. This work could be used to improve the efficiency of photoluminescence and random lasing emissions, and it is promising in high-performance optoelectrical devices. Full article

(This article belongs to the Topic Organic and Perovskite Optoelectronic Materials and Devices)

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12 pages, 6609 KiB

Open AccessEditor’s ChoiceArticle

One-Step Electrochemical Dealloying of 3D Bi-Continuous Micro-Nanoporous Bismuth Electrodes and CO₂RR Performance

by Wenqin Lai, Yating Liu, Mingming Zeng, Dongmei Han, Min Xiao, Shuanjin Wang, Shan Ren and Yuezhong Meng

Nanomaterials 2023, 13(11), 1767; https://doi.org/10.3390/nano13111767 - 30 May 2023

Cited by 2 | Viewed by 1585

Abstract

The rapid development of electrochemical CO₂ reduction offers a promising route to convert intermittent renewable energy into products of high value-added fuels or chemical feedstocks. However, low faradaic efficiency, low current density, and a narrow potential range still limit the large-scale application [...] Read more.

The rapid development of electrochemical CO₂ reduction offers a promising route to convert intermittent renewable energy into products of high value-added fuels or chemical feedstocks. However, low faradaic efficiency, low current density, and a narrow potential range still limit the large-scale application of CO₂RR electrocatalysts. Herein, monolith 3D bi-continuous nanoporous bismuth (np-Bi) electrodes are fabricated via a simple one-step electrochemical dealloying strategy from Pb-Bi binary alloy. The unique bi-continuous porous structure ensures highly effective charge transfer; meanwhile, the controllable millimeter-sized geometric porous structure enables easy catalyst adjustment to expose highly suitable surface curvatures with abundant reactive sites. This results in a high selectivity of 92.6% and superior potential window (400 mV, selectivity > 88%) for the electrochemical reduction of carbon dioxide to formate. Our scalable strategy provides a feasible pathway for mass-producing high-performance and versatile CO₂ electrocatalysts. Full article

(This article belongs to the Special Issue Modification Strategies on Engineering Electrocatalysts Related to Nanomaterials)

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23 pages, 12431 KiB

Open AccessEditor’s ChoiceReview

Carbon Nanocomposites in Aerospace Technology: A Way to Protect Low-Orbit Satellites

by Janith Weerasinghe, Karthika Prasad, Joice Mathew, Eduardo Trifoni, Oleg Baranov, Igor Levchenko and Kateryna Bazaka

Nanomaterials 2023, 13(11), 1763; https://doi.org/10.3390/nano13111763 - 30 May 2023

Cited by 8 | Viewed by 4529

Abstract

Recent advancements in space technology and reduced launching cost led companies, defence and government organisations to turn their attention to low Earth orbit (LEO) and very low Earth orbit (VLEO) satellites, for they offer significant advantages over other types of spacecraft and present [...] Read more.

Recent advancements in space technology and reduced launching cost led companies, defence and government organisations to turn their attention to low Earth orbit (LEO) and very low Earth orbit (VLEO) satellites, for they offer significant advantages over other types of spacecraft and present an attractive solution for observation, communication and other tasks. However, keeping satellites in LEO and VLEO presents a unique set of challenges, in addition to those typically associated with exposure to space environment such as damage from space debris, thermal fluctuations, radiation and thermal management in vacuum. The structural and functional elements of LEO and especially VLEO satellites are significantly affected by residual atmosphere and, in particular, atomic oxygen (AO). At VLEO, the remaining atmosphere is dense enough to create significant drag and quicky de-orbit satellites; thus, thrusters are needed to keep them on a stable orbit. Atomic oxygen-induced material erosion is another key challenge to overcome during the design phase of LEO and VLEO spacecraft. This review covered the corrosion interactions between the satellites and the low orbit environment, and how it can be minimised through the use of carbon-based nanomaterials and their composites. The review also discussed key mechanisms and challenges underpinning material design and fabrication, and it outlined the current research in this area. Full article

(This article belongs to the Special Issue Nanomaterials for Potential Uses in Extraterrestrial Environments)

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15 pages, 2658 KiB

Open AccessEditor’s ChoiceArticle

High-Performance Perovskite Solar Cells and Modules Fabricated by Slot-Die Coating with Nontoxic Solvents

by Chia-Feng Li, Hung-Che Huang, Shih-Han Huang, Yu-Hung Hsiao, Priyanka Chaudhary, Chun-Yu Chang, Feng-Yu Tsai, Wei-Fang Su and Yu-Ching Huang

Nanomaterials 2023, 13(11), 1760; https://doi.org/10.3390/nano13111760 - 29 May 2023

Cited by 4 | Viewed by 2530

Abstract

Energy shortage has become a global issue in the twenty-firt century, as energy consumption grows at an alarming rate as the fossil fuel supply exhausts. Perovskite solar cells (PSCs) are a promising photovoltaic technology that has grown quickly in recent years. Its power [...] Read more.

Energy shortage has become a global issue in the twenty-firt century, as energy consumption grows at an alarming rate as the fossil fuel supply exhausts. Perovskite solar cells (PSCs) are a promising photovoltaic technology that has grown quickly in recent years. Its power conversion efficiency (PCE) is comparable to that of traditional silicon-based solar cells, and scale-up costs can be substantially reduced due to its utilization of solution-processable fabrication. Nevertheless, most PSCs research uses hazardous solvents, such as dimethylformamide (DMF) and chlorobenzene (CB), which are not suitable for large-scale ambient operations and industrial production. In this study, we have successfully deposited all of the layers of PSCs, except the top metal electrode, under ambient conditions using a slot-die coating process and nontoxic solvents. The fully slot-die coated PSCs exhibited PCEs of 13.86% and 13.54% in a single device (0.09 cm²) and mini-module (0.75 cm²), respectively. Full article

(This article belongs to the Special Issue Nanomaterials and Nanofabrication for Solar Cells and Energy Harvesting)

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21 pages, 14746 KiB

Open AccessEditor’s ChoiceArticle

Enhancing Functionalization of Health Care Textiles with Gold Nanoparticle-Loaded Hydroxyapatite Composites

by Bárbara Vieira, Jorge Padrão, Cátia Alves, Carla Joana Silva, Helena Vilaça and Andrea Zille

Nanomaterials 2023, 13(11), 1752; https://doi.org/10.3390/nano13111752 - 27 May 2023

Cited by 2 | Viewed by 1781

Abstract

Hospitals and nursing home wards are areas prone to the propagation of infections and are of particular concern regarding the spreading of dangerous viruses and multidrug-resistant bacteria (MDRB). MDRB infections comprise approximately 20% of cases in hospitals and nursing homes. Healthcare textiles, such [...] Read more.

Hospitals and nursing home wards are areas prone to the propagation of infections and are of particular concern regarding the spreading of dangerous viruses and multidrug-resistant bacteria (MDRB). MDRB infections comprise approximately 20% of cases in hospitals and nursing homes. Healthcare textiles, such as blankets, are ubiquitous in hospitals and nursing home wards and may be easily shared between patients/users without an adequate pre-cleaning process. Therefore, functionalizing these textiles with antimicrobial properties may considerably reduce the microbial load and prevent the propagation of infections, including MDRB. Blankets are mainly comprised of knitted cotton (CO), polyester (PES), and cotton-polyester (CO–PES). These fabrics were functionalized with novel gold-hydroxyapatite nanoparticles (AuNPs-HAp) that possess antimicrobial properties, due to the presence of the AuNPs’ amine and carboxyl groups, and low propensity to display toxicity. For optimal functionalization of the knitted fabrics, two pre-treatments, four different surfactants, and two incorporation processes were evaluated. Furthermore, exhaustion parameters (time and temperature) were subjected to a design of experiments (DoE) optimization. The concentration of AuNPs-HAp in the fabrics and their washing fastness were critical factors assessed through color difference (ΔE). The best performing knitted fabric was half bleached CO, functionalized using a surfactant combination of Imerol^® Jet-B (surfactant A) and Luprintol^® Emulsifier PE New (surfactant D) through exhaustion at 70 °C for 10 min. This knitted CO displayed antibacterial properties even after 20 washing cycles, showing its potential to be used in comfort textiles within healthcare environments. Full article

(This article belongs to the Section Nanocomposite Materials)

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15 pages, 1247 KiB

Open AccessEditor’s ChoiceArticle

The Key Role of Non-Local Screening in the Environment-Insensitive Exciton Fine Structures of Transition-Metal Dichalcogenide Monolayers

by Wei-Hua Li, Jhen-Dong Lin, Ping-Yuan Lo, Guan-Hao Peng, Ching-Yu Hei, Shao-Yu Chen and Shun-Jen Cheng

Nanomaterials 2023, 13(11), 1739; https://doi.org/10.3390/nano13111739 - 26 May 2023

Cited by 5 | Viewed by 2825

Abstract

In this work, we present a comprehensive theoretical and computational investigation of exciton fine structures of WSe

_{2}

-monolayers, one of the best-known two-dimensional (2D) transition-metal dichalcogenides (TMDs), in various dielectric-layered environments by solving the first-principles-based Bethe–Salpeter equation. While the physical and electronic [...] Read more.

In this work, we present a comprehensive theoretical and computational investigation of exciton fine structures of WSe

_{2}

-monolayers, one of the best-known two-dimensional (2D) transition-metal dichalcogenides (TMDs), in various dielectric-layered environments by solving the first-principles-based Bethe–Salpeter equation. While the physical and electronic properties of atomically thin nanomaterials are normally sensitive to the variation of the surrounding environment, our studies reveal that the influence of the dielectric environment on the exciton fine structures of TMD-MLs is surprisingly limited. We point out that the non-locality of Coulomb screening plays a key role in suppressing the dielectric environment factor and drastically shrinking the fine structure splittings between bright exciton (BX) states and various dark-exciton (DX) states of TMD-MLs. The intriguing non-locality of screening in 2D materials can be manifested by the measurable non-linear correlation between the BX-DX splittings and exciton-binding energies by varying the surrounding dielectric environments. The revealed environment-insensitive exciton fine structures of TMD-ML suggest the robustness of prospective dark-exciton-based optoelectronics against the inevitable variation of the inhomogeneous dielectric environment. Full article

(This article belongs to the Special Issue Excitons and Phonons in Two-Dimensional Materials: From Fundamental to Applications)

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29 pages, 6626 KiB

Open AccessEditor’s ChoiceReview

Research Progress on Metal–Organic Frameworks by Advanced Transmission Electron Microscopy

by Anqi Zheng, Kuibo Yin, Rui Pan, Mingyun Zhu, Yuwei Xiong and Litao Sun

Nanomaterials 2023, 13(11), 1742; https://doi.org/10.3390/nano13111742 - 26 May 2023

Cited by 8 | Viewed by 3728

Abstract

Metal–organic frameworks (MOFs), composed of metal nodes and inorganic linkers, are promising for a wide range of applications due to their unique periodic frameworks. Understanding structure–activity relationships can facilitate the development of new MOFs. Transmission electron microscopy (TEM) is a powerful technique to [...] Read more.

Metal–organic frameworks (MOFs), composed of metal nodes and inorganic linkers, are promising for a wide range of applications due to their unique periodic frameworks. Understanding structure–activity relationships can facilitate the development of new MOFs. Transmission electron microscopy (TEM) is a powerful technique to characterize the microstructures of MOFs at the atomic scale. In addition, it is possible to directly visualize the microstructural evolution of MOFs in real time under working conditions via in situ TEM setups. Although MOFs are sensitive to high-energy electron beams, much progress has been made due to the development of advanced TEM. In this review, we first introduce the main damage mechanisms for MOFs under electron-beam irradiation and two strategies to minimize these damages: low-dose TEM and cryo-TEM. Then we discuss three typical techniques to analyze the microstructure of MOFs, including three-dimensional electron diffraction, imaging using direct-detection electron-counting cameras, and iDPC-STEM. Groundbreaking milestones and research advances of MOFs structures obtained with these techniques are highlighted. In situ TEM studies are reviewed to provide insights into the dynamics of MOFs induced by various stimuli. Additionally, perspectives are analyzed for promising TEM techniques in the research of MOFs’ structures. Full article

(This article belongs to the Section Inorganic Materials and Metal-Organic Frameworks)

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23 pages, 5753 KiB

Open AccessEditor’s ChoiceReview

Recent Advances in Nanomaterial-Based Chemiluminescence Probes for Biosensing and Imaging of Reactive Oxygen Species

by Chuanlin Huang, Wenjuan Zhou, Riliga Wu, Weijiang Guan and Nengsheng Ye

Nanomaterials 2023, 13(11), 1726; https://doi.org/10.3390/nano13111726 - 25 May 2023

Cited by 7 | Viewed by 2139

Abstract

Reactive oxygen species (ROS) play important roles in organisms and are closely related to various physiological and pathological processes. Due to the short lifetime and easy transformation of ROS, the determination of ROS content in biosystem has always been a challenging task. Chemiluminescence [...] Read more.

Reactive oxygen species (ROS) play important roles in organisms and are closely related to various physiological and pathological processes. Due to the short lifetime and easy transformation of ROS, the determination of ROS content in biosystem has always been a challenging task. Chemiluminescence (CL) analysis has been widely used in the detection of ROS due to its advantages of high sensitivity, good selectivity and no background signal, among which nanomaterial-related CL probes are rapidly developing. In this review, the roles of nanomaterials in CL systems are summarized, mainly including their roles as catalysts, emitters, and carriers. The nanomaterial-based CL probes for biosensing and bioimaging of ROS developed in the past five years are reviewed. We expect that this review will provide guidance for the design and development of nanomaterial-based CL probes and facilitate the wider application of CL analysis in ROS sensing and imaging in biological systems. Full article

(This article belongs to the Topic Photosensitive and Optical Materials)

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15 pages, 3159 KiB

Open AccessEditor’s ChoiceArticle

High-Dose Exposure to Polymer-Coated Iron Oxide Nanoparticles Elicits Autophagy-Dependent Ferroptosis in Susceptible Cancer Cells

by Thanpisit Lomphithak, Selin Helvacioglu, Ilaria Armenia, Sandeep Keshavan, Jesús G. Ovejero, Giovanni Baldi, Costanza Ravagli, Valeria Grazú and Bengt Fadeel

Nanomaterials 2023, 13(11), 1719; https://doi.org/10.3390/nano13111719 - 24 May 2023

Cited by 7 | Viewed by 2383

Abstract

Ferroptosis, a form of iron-dependent, lipid peroxidation-driven cell death, has been extensively investigated in recent years, and several studies have suggested that the ferroptosis-inducing properties of iron-containing nanomaterials could be harnessed for cancer treatment. Here we evaluated the potential cytotoxicity of iron oxide [...] Read more.

Ferroptosis, a form of iron-dependent, lipid peroxidation-driven cell death, has been extensively investigated in recent years, and several studies have suggested that the ferroptosis-inducing properties of iron-containing nanomaterials could be harnessed for cancer treatment. Here we evaluated the potential cytotoxicity of iron oxide nanoparticles, with and without cobalt functionalization (Fe₂O₃ and Fe₂O₃@Co-PEG), using an established, ferroptosis-sensitive fibrosarcoma cell line (HT1080) and a normal fibroblast cell line (BJ). In addition, we evaluated poly (ethylene glycol) (PEG)-poly(lactic-co-glycolic acid) (PLGA)-coated iron oxide nanoparticles (Fe₃O₄-PEG-PLGA). Our results showed that all the nanoparticles tested were essentially non-cytotoxic at concentrations up to 100 μg/mL. However, when the cells were exposed to higher concentrations (200–400 μg/mL), cell death with features of ferroptosis was observed, and this was more pronounced for the Co-functionalized nanoparticles. Furthermore, evidence was provided that the cell death triggered by the nanoparticles was autophagy-dependent. Taken together, the exposure to high concentrations of polymer-coated iron oxide nanoparticles triggers ferroptosis in susceptible human cancer cells. Full article

(This article belongs to the Special Issue Interaction of Nanomaterials with Biological Systems: In Vitro and In Vivo Studies)

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12 pages, 2731 KiB

Open AccessEditor’s ChoiceArticle

A Flexible Piezocapacitive Pressure Sensor with Microsphere-Array Electrodes

by Shu Ying, Jiean Li, Jinrong Huang, Jia-Han Zhang, Jing Zhang, Yongchang Jiang, Xidi Sun, Lijia Pan and Yi Shi

Nanomaterials 2023, 13(11), 1702; https://doi.org/10.3390/nano13111702 - 23 May 2023

Cited by 6 | Viewed by 3531

Abstract

Flexible pressure sensors that emulate the sensation and characteristics of natural skins are of great importance in wearable medical devices, intelligent robots, and human–machine interfaces. The microstructure of the pressure-sensitive layer plays a significant role in the sensor’s overall performance. However, microstructures usually [...] Read more.

Flexible pressure sensors that emulate the sensation and characteristics of natural skins are of great importance in wearable medical devices, intelligent robots, and human–machine interfaces. The microstructure of the pressure-sensitive layer plays a significant role in the sensor’s overall performance. However, microstructures usually require complex and costly processes such as photolithography or chemical etching for fabrication. This paper proposes a novel approach that combines self-assembled technology to prepare a high-performance flexible capacitive pressure sensor with a microsphere-array gold electrode and a nanofiber nonwoven dielectric material. When subjected to pressure, the microsphere structures of the gold electrode deform via compressing the medium layer, leading to a significant increase in the relative area between the electrodes and a corresponding change in the thickness of the medium layer, as simulated in COMSOL simulations and experiments, which presents high sensitivity (1.807 kPa⁻¹). The developed sensor demonstrates excellent performance in detecting signals such as slight object deformations and human finger bending. Full article

(This article belongs to the Special Issue Amorphous and Nanocrystalline Semiconductors: Selected Papers from ICANS 29)

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15 pages, 3886 KiB

Open AccessEditor’s ChoiceArticle

Peroxidase-Mimicking Ir-Te Nanorods for Photoconversion-Combined Multimodal Cancer Therapy

by Gyeonghye Yim, Seounghun Kang, Subean Kim and Hongje Jang

Nanomaterials 2023, 13(11), 1706; https://doi.org/10.3390/nano13111706 - 23 May 2023

Viewed by 1636

Abstract

Owing to multiple physicochemical properties, the combination of hybrid elemental compositions of nanoparticles can be widely utilized for a variety of applications. To combine pristine tellurium nanorods, which act as a sacrificing template, with another element, iridium–tellurium nanorods (IrTeNRs) were synthesized via the [...] Read more.

Owing to multiple physicochemical properties, the combination of hybrid elemental compositions of nanoparticles can be widely utilized for a variety of applications. To combine pristine tellurium nanorods, which act as a sacrificing template, with another element, iridium–tellurium nanorods (IrTeNRs) were synthesized via the galvanic replacement technique. Owing to the coexistence of iridium and tellurium, IrTeNRs exhibited unique properties, such as peroxidase-like activity and photoconversion. Additionally, the IrTeNRs demonstrated exceptional colloidal stability in complete media. Based on these properties, the IrTeNRs were applied to in vitro and in vivo cancer therapy, allowing for the possibility of multiple therapeutic methodologies. The enzymatic therapy was enabled by the peroxidase-like activity that generated reactive oxygen species, and the photoconversion under 473, 660 and 808 nm laser irradiation induced cancer cell apoptosis via photothermal and photodynamic therapy. Full article

(This article belongs to the Section Synthesis, Interfaces and Nanostructures)

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10 pages, 536 KiB

Open AccessEditor’s ChoiceArticle

Cone-Shell Quantum Structures in Electric and Magnetic Fields as Switchable Traps for Photoexcited Charge Carriers

by Christian Heyn, Leonardo Ranasinghe, Ahmed Alshaikh and Carlos A. Duque

Nanomaterials 2023, 13(10), 1696; https://doi.org/10.3390/nano13101696 - 22 May 2023

Cited by 1 | Viewed by 1125

Abstract

The optical emission of cone-shell quantum structures (CSQS) under vertical electric (F) and magnetic (B) fields is studied by means of simulations. A CSQS has a unique shape, where an electric field induces the transformation of the hole probability [...] Read more.

The optical emission of cone-shell quantum structures (CSQS) under vertical electric (F) and magnetic (B) fields is studied by means of simulations. A CSQS has a unique shape, where an electric field induces the transformation of the hole probability density from a disk into a quantum-ring with a tunable radius. The present study addresses the influence of an additional magnetic field. A common description for the influence of a B-field on charge carriers confined in a quantum dot is the Fock-Darwin model, which introduces the angular momentum quantum number l to describe the splitting of the energy levels. For a CSQS with the hole in the quantum ring state, the present simulations demonstrate a B-dependence of the hole energy which substantially deviates from the prediction of the Fock-Darwin model. In particular, the energy of exited states with a hole

l_{h} >

0 can become lower than the ground state energy with

l_{h} =

0. Because for the lowest-energy state the electron

l_{e}

is always zero, states with

l_{h} >

0 are optically dark due to selection rules. This allows switching from a bright state (

l_{h} =

0) to a dark state (

l_{h} >

0) or vice versa by changing the strength of the F or B field. This effect can be very interesting for trapping photoexcited charge carriers for a desired time. Furthermore, the influence of the CSQS shape on the fields required for the bright to dark state transition is investigated. Full article

(This article belongs to the Special Issue Photoemission and Excitation Properties of Nanomaterials by Computational Methods)

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21 pages, 3894 KiB

Open AccessEditor’s ChoiceReview

Advances in Solution-Processed Blue Quantum Dot Light-Emitting Diodes

by Sheng-Nan Li, Jia-Lin Pan, Yan-Jun Yu, Feng Zhao, Ya-Kun Wang and Liang-Sheng Liao

Nanomaterials 2023, 13(10), 1695; https://doi.org/10.3390/nano13101695 - 22 May 2023

Cited by 8 | Viewed by 4221

Abstract

Quantum dot light-emitting diodes (QLEDs) have been identified as a next-generation display technology owing to their low-cost manufacturing, wide color gamut, and electrically driven self-emission properties. However, the efficiency and stability of blue QLEDs still pose a significant challenge, limiting their production and [...] Read more.

Quantum dot light-emitting diodes (QLEDs) have been identified as a next-generation display technology owing to their low-cost manufacturing, wide color gamut, and electrically driven self-emission properties. However, the efficiency and stability of blue QLEDs still pose a significant challenge, limiting their production and potential application. This review aims to analyse the factors leading to the failure of blue QLEDs and presents a roadmap to accelerate their development based on the progress made in the synthesis of II-VI (CdSe, ZnSe) quantum dots (QDs), III-V (InP) QDs, carbon dots, and perovskite QDs. The proposed analysis will include discussions on material synthesis, core-shell structures, ligand interactions, and device fabrication, providing a comprehensive overview of these materials and their development. Full article

(This article belongs to the Special Issue Semiconductor Quantum Dots: Synthesis, Properties and Applications)

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15 pages, 10906 KiB

Open AccessEditor’s ChoiceArticle

Multi-Scale Femtosecond-Laser Texturing for Photothermal Efficiency Enhancement on Solar Absorbers Based on TaB₂ Ceramics

by Elisa Sani, Diletta Sciti, Simone Failla, Cesare Melandri, Alessandro Bellucci, Stefano Orlando and Daniele M. Trucchi

Nanomaterials 2023, 13(10), 1692; https://doi.org/10.3390/nano13101692 - 21 May 2023

Cited by 6 | Viewed by 1477

Abstract

Tantalum boride is an ultra-refractory and ultra-hard ceramic known so far for its favorable high-temperature thermo-mechanical properties and also characterized by a low spectral emittance, making it interesting for novel high-temperature solar absorbers for Concentrating Solar Power. In this work, we investigated two [...] Read more.

Tantalum boride is an ultra-refractory and ultra-hard ceramic known so far for its favorable high-temperature thermo-mechanical properties and also characterized by a low spectral emittance, making it interesting for novel high-temperature solar absorbers for Concentrating Solar Power. In this work, we investigated two types of TaB₂ sintered products with different porosities, and on each of them, we realized four femtosecond laser treatments differing in the accumulated laser fluence. The treated surfaces were then characterized by SEM-EDS, roughness analysis, and optical spectrometry. We show that, depending on laser processing parameters, the multi-scale surface textures produced by femtosecond laser machining can greatly increase the solar absorptance, while the spectral emittance increase is significantly lower. These combined effects result in increased photothermal efficiency of the absorber, with interesting perspectives for the application of these ceramics in Concentrating Solar Power and Concentrating Solar Thermal. To the best of our knowledge, this is the first demonstration of successful photothermal efficiency enhancement of ultra-hard ceramics using laser machining. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Renewable Energies and Technical Applications)

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12 pages, 3294 KiB

Open AccessEditor’s ChoiceArticle

Effect of High-Energy Ball Milling, Capping Agents and Alkalizer on Capacitance of Nanostructured FeOOH Anodes

by Chengwei Zhang and Igor Zhitomirsky

Nanomaterials 2023, 13(10), 1693; https://doi.org/10.3390/nano13101693 - 21 May 2023

Viewed by 1501

Abstract

This investigation is motivated by interest in nanostructured FeOOH anodes for aqueous asymmetric supercapacitors operating in Na₂SO₄ electrolyte. The research goal is the fabrication of anodes with high active mass loading of 40 mg cm⁻², high capacitance and [...] Read more.

This investigation is motivated by interest in nanostructured FeOOH anodes for aqueous asymmetric supercapacitors operating in Na₂SO₄ electrolyte. The research goal is the fabrication of anodes with high active mass loading of 40 mg cm⁻², high capacitance and low resistance. The influence of high-energy ball milling (HEBM), capping agents and alkalizer on the nanostructure and capacitive properties is investigated. HEBM promotes the crystallization of FeOOH, which results in capacitance reduction. Capping agents from the catechol family, such as tetrahydroxy-1,4-benzoquinone (THB) and gallocyanine (GC), facilitate the fabrication of FeOOH nanoparticles, eliminate the formation of micron size particles and allow the fabrication of anodes with enhanced capacitance. The analysis of testing results provided insight into the influence of the chemical structure of the capping agents on nanoparticle synthesis and dispersion. The feasibility of a conceptually new strategy for the synthesis of FeOOH nanoparticles is demonstrated, which is based on the use of polyethylenimine as an organic alkalizer-dispersant. The capacitances of materials prepared using different nanotechnology strategies are compared. The highest capacitance of 6.54 F cm⁻² is obtained using GC as a capping agent. The obtained electrodes are promising for applications as anodes for asymmetric supercapacitors. Full article

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14 pages, 2653 KiB

Open AccessEditor’s ChoiceArticle

Photoelectrochemical Selective Oxidation of Glycerol to Glyceraldehyde with Bi-Based Metal–Organic-Framework-Decorated WO₃ Photoanode

by Yoonsung Jung, Seungkyu Kim, Hojoong Choi, Yunseul Kim, Jun Beom Hwang, Donghyeon Lee, Yejoon Kim, Jun-Cheol Park, Dong-Yu Kim and Sanghan Lee

Nanomaterials 2023, 13(10), 1690; https://doi.org/10.3390/nano13101690 - 21 May 2023

Cited by 6 | Viewed by 3223

Abstract

The conversion of glycerol to high-value-added products via photoelectrochemical (PEC) oxidation has emerged as a promising approach for utilizing a sustainable and clean energy source with environmental and economic benefits. Moreover, the energy requirement for glycerol to produce hydrogen is lower than that [...] Read more.

The conversion of glycerol to high-value-added products via photoelectrochemical (PEC) oxidation has emerged as a promising approach for utilizing a sustainable and clean energy source with environmental and economic benefits. Moreover, the energy requirement for glycerol to produce hydrogen is lower than that for pure water splitting. In this study, we propose the use of WO₃ nanostructures decorated with Bi-based metal–organic frameworks (Bi-MOFs) as the photoanode for glycerol oxidation with simultaneous hydrogen production. The WO₃-based electrodes selectively converted glycerol to glyceraldehyde, a high-value-added product, with remarkable selectivity. The Bi-MOF-decorated WO₃ nanorods enhanced the surface charge transfer and adsorption properties, thereby improving the photocurrent density and production rate (1.53 mA/cm² and 257 mmol/m²·h at 0.8 V_RHE). The photocurrent was maintained for 10 h, ensuring stable glycerol conversion. Furthermore, at 1.2 V_RHE, the average production rate of glyceraldehyde reached 420 mmol/m²·h, with a selectivity of 93.6% between beneficial oxidized products over the photoelectrode. This study provides a practical approach for the conversion of glycerol to glyceraldehyde via the selective oxidation of WO₃ nanostructures and demonstrates the potential of Bi-MOFs as a promising cocatalyst for PEC biomass valorization. Full article

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14 pages, 3450 KiB

Open AccessEditor’s ChoiceArticle

Research on an Optimized Quarter-Wavelength Resonator-Based Triboelectric Nanogenerator for Efficient Low-Frequency Acoustic Energy Harvesting

by Xiu Xiao, Ling Liu, Ziyue Xi, Hongyong Yu, Wenxiang Li, Qunyi Wang, Cong Zhao, Yue Huang and Minyi Xu

Nanomaterials 2023, 13(10), 1676; https://doi.org/10.3390/nano13101676 - 19 May 2023

Cited by 7 | Viewed by 1960

Abstract

Sound wave is an extensively existing mechanical wave, especially in marine and industrial plants where low-frequency acoustic waves are ubiquitous. The effective collection and utilization of sound waves provide a fresh new approach to supply power for the distributed nodes of the rapidly [...] Read more.

Sound wave is an extensively existing mechanical wave, especially in marine and industrial plants where low-frequency acoustic waves are ubiquitous. The effective collection and utilization of sound waves provide a fresh new approach to supply power for the distributed nodes of the rapidly developing Internet of Things technology. In this paper, a novel acoustic triboelectric nanogenerator (QWR-TENG) was proposed for efficient low-frequency acoustic energy harvesting. QWR-TENG consisted of a quarter-wavelength resonant tube, a uniformly perforated aluminum film, an FEP membrane, and a conductive carbon nanotube coating. Simulation and experimental studies showed that QWR-TENG has two resonance peaks in the low-frequency range, which effectively extends the response bandwidth of acoustic–electrical conversion. The structural optimized QWR-TENG has excellent electrical output performance, and the maximum output voltage, short-circuit current and transferred charge are 255 V, 67 μA, and 153 nC, respectively, under the acoustic frequency of 90 Hz and sound pressure level of 100 dB. On this basis, a conical energy concentrator was introduced to the entrance of the acoustic tube, and a composite quarter-wavelength resonator-based triboelectric nanogenerator (CQWR-TENG) was designed to further enhance the electrical output. Results showed that the maximum output power and the power density per unit pressure of CQWR-TENG reached 13.47 mW and 2.27 WPa⁻¹m⁻², respectively. Application demonstrations indicated that QWR/CQWR-TENG has good capacitor charging performance and is expected to realize power supply for distributed sensor nodes and other small electrical devices. Full article

(This article belongs to the Special Issue Advance in Energy Harvesters/Nanogenerators and Self-Powered Sensors II)

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13 pages, 6329 KiB

Open AccessEditor’s ChoiceArticle

Monolithic MXene Aerogels Encapsulated Phase Change Composites with Superior Photothermal Conversion and Storage Capability

by Yan Wang, Fuqiang Wang, Changrui Shi, Hongsheng Dong, Yongchen Song, Jiafei Zhao and Zheng Ling

Nanomaterials 2023, 13(10), 1661; https://doi.org/10.3390/nano13101661 - 17 May 2023

Cited by 2 | Viewed by 1922

Abstract

The inherently intermittent feature of solar energy requires reliable energy conversion and storage systems for utilizing the most abundant solar energy. Phase change materials are potential solutions to store a large amount of heat produced by solar light. However, few of the phase [...] Read more.

The inherently intermittent feature of solar energy requires reliable energy conversion and storage systems for utilizing the most abundant solar energy. Phase change materials are potential solutions to store a large amount of heat produced by solar light. However, few of the phase change materials have the ability to efficiently convert solar energy into heat; additionally, phase change materials need to be encapsulated in porous substrates for enhancing their leaking resistance and photo-to-thermal performance. In this work, monolithic MXene aerogels, fabricated by Al³⁺ cross-linking and freeze-drying, were used as the encapsulation and photothermal materials. The composites phase change materials of MXene/polyethylene glycol can be made with a large polyethylene glycol loading above 90 wt% with the maximum of 97 wt%, owing to the large porosity of MXene aerogels. The low content of MXene has a limited impact on the phase transition temperature and enthalpy of polyethylene glycol, with an enthalpy retention rate ranging from 89.2 to 96.5% for 90–97 wt% polyethylene glycol loadings. MXene aerogels greatly improve the leaking resistance of polyethylene glycol above its melting point of 60 °C, even at 100 °C. The composites phase change materials also show outstanding cycling stability for 500 cycles of heat storage and release, retaining 97.7% of the heat storage capability. The optimized composite phase change material has a solar energy utilization of 93.5%, being superior to most of the reported results. Our strategy produces promising composite phase change materials for solar energy utilization using the MXene aerogels as the encapsulation and photothermal materials. Full article

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10 pages, 3049 KiB

Open AccessEditor’s ChoiceArticle

Optical and Electrical Analyses of Solar Cells with a Radial PN Junction and Incorporating an Innovative NW Design That Mimics ARC Layers

by Francisco J. Cabrera-España and B. M. Azizur Rahman

Nanomaterials 2023, 13(10), 1649; https://doi.org/10.3390/nano13101649 - 16 May 2023

Viewed by 1239

Abstract

The implementation of a texturing pattern on the surface of a solar cell is well known for reducing reflection, thus increasing the absorption of sunlight by the solar cell. Nanowires (NWs) that are large in their height have been widely used for this [...] Read more.

The implementation of a texturing pattern on the surface of a solar cell is well known for reducing reflection, thus increasing the absorption of sunlight by the solar cell. Nanowires (NWs) that are large in their height have been widely used for this purpose. Through rigorous numerical simulations, this work explores the benefits of short but index-matched NWs and how these designs are also affected by surface recombination. Additionally, this work further optimized power conversion efficiency (PCE) by placing two or three NWs of different heights and diameters on top of each other to mimic the performance of two-NW and three-NW ARC designs with PCEs of 16.8% and 17.55%, respectively, when a radial pn junction is considered. These are the highest reported so far for such a thin silicon solar cell. Furthermore, we also show how these designs were impacted by surface recombination velocity and compare these findings to simple NWs of different heights and diameters. Full article

(This article belongs to the Special Issue Recent Advances on Photovoltaics and Solar Cells)

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18 pages, 9066 KiB

Open AccessEditor’s ChoiceArticle

Variation in Metal–Support Interaction with TiO₂ Loading and Synthesis Conditions for Pt-Ti/SBA-15 Active Catalysts in Methane Combustion

by Mihaela Filip, Elena Maria Anghel, Vasile Rednic, Florica Papa, Simona Somacescu, Cornel Munteanu, Nicolae Aldea, Jing Zhang and Viorica Parvulescu

Nanomaterials 2023, 13(10), 1647; https://doi.org/10.3390/nano13101647 - 15 May 2023

Cited by 2 | Viewed by 1606

Abstract

The control of catalytic performance using synthesis conditions is one of the main goals of catalytic research. Two series of Pt-Ti/SBA-15 catalysts with different TiO₂ percentages (n = 1, 5, 10, 30 wt.%) were obtained from tetrabutylorthotitanate (TBOT) and peroxotitanate (PT), [...] Read more.

The control of catalytic performance using synthesis conditions is one of the main goals of catalytic research. Two series of Pt-Ti/SBA-15 catalysts with different TiO₂ percentages (n = 1, 5, 10, 30 wt.%) were obtained from tetrabutylorthotitanate (TBOT) and peroxotitanate (PT), as titania precursors and Pt impregnation. The obtained catalysts were characterized using X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), N₂ sorption, Raman, X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), hydrogen temperature-programmed reduction (H₂-TPR) and H₂-chemisorption measurements. Raman spectroscopy showed framework titanium species in low TiO₂ loading samples. The anatase phase was evidenced for samples with higher titania loading, obtained from TBOT, and a mixture of rutile and anatase for those synthesized by PT. The rutile phase prevails in rich TiO₂ catalysts obtained from PT. Variable concentrations of Pt⁰ as a result of the stronger interaction of PtO with anatase and the weaker interaction with rutile were depicted using XPS. TiO₂ loading and precursors influenced the concentration of Pt species, while the effect on Pt nanoparticles’ size and uniform distribution on support was insignificant. The Pt/PtO ratio and their concentration on the surface were the result of strong metal–support interaction, and this influenced catalytic performance in the complete oxidation of methane at a low temperature. The highest conversion was obtained for sample prepared from PT with 30% TiO₂. Full article

(This article belongs to the Special Issue Recent Advancements in Mesoporous Nanomaterials: Synthesis, Characterization and Catalytic Applications)

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27 pages, 4583 KiB

Open AccessEditor’s ChoiceReview

Recent Advances in Tunable Metasurfaces and Their Application in Optics

by Alberto Santonocito, Barbara Patrizi and Guido Toci

Nanomaterials 2023, 13(10), 1633; https://doi.org/10.3390/nano13101633 - 13 May 2023

Cited by 7 | Viewed by 6788

Abstract

Metasurfaces can be opportunely and specifically designed to manipulate electromagnetic wavefronts. In recent years, a large variety of metasurface-based optical devices such as planar lenses, beam deflectors, polarization converters, and so on have been designed and fabricated. Of particular interest are tunable metasurfaces, [...] Read more.

Metasurfaces can be opportunely and specifically designed to manipulate electromagnetic wavefronts. In recent years, a large variety of metasurface-based optical devices such as planar lenses, beam deflectors, polarization converters, and so on have been designed and fabricated. Of particular interest are tunable metasurfaces, which allow the modulation of the optical response of a metasurface; for instance, the variation in the focal length of a converging metalens. Response tunability can be achieved through external sources that modify the permittivity of the materials constituting the nanoatoms, the substrate, or both. The modulation sources can be classified into electromagnetic fields, thermal sources, mechanical stressors, and electrical bias. Beside this, we will consider optical modulation and multiple approach tuning strategies. A great variety of tunable materials have been used in metasurface engineering, such as transparent conductive oxides, ferroelectrics, phase change materials, liquid crystals, and semiconductors. The possibility of tuning the optical properties of these metamaterials is very important for several applications spanning from basic optics to applied optics for communications, depth sensing, holographic displays, and biochemical sensors. In this review, we summarize the recent progress on electro-optical magnetic, mechanical, and thermal tuning of metasurfaces actually fabricated and experimentally tested in recent years. At the end of the review, a short section on possible future perspectives and applications is included. Full article

(This article belongs to the Special Issue Metasurfaces for Photonic Devices: Theory and Applications)

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12 pages, 2144 KiB

Open AccessEditor’s ChoiceArticle

Inductively Coupled Nonthermal Plasma Synthesis of Size-Controlled γ-Al₂O₃ Nanocrystals

by Zichang Xiong, Himashi P. Andaraarachchi, Jacob T. Held, Rick W. Dorn, Yong-Jin Jeong, Aaron Rossini and Uwe R. Kortshagen

Nanomaterials 2023, 13(10), 1627; https://doi.org/10.3390/nano13101627 - 12 May 2023

Cited by 1 | Viewed by 1575

Abstract

Gamma alumina (γ-Al₂O₃) is widely used as a catalyst and catalytic support due to its high specific surface area and porosity. However, synthesis of γ-Al₂O₃ nanocrystals is often a complicated process requiring high temperatures or additional [...] Read more.

Gamma alumina (γ-Al₂O₃) is widely used as a catalyst and catalytic support due to its high specific surface area and porosity. However, synthesis of γ-Al₂O₃ nanocrystals is often a complicated process requiring high temperatures or additional post-synthetic steps. Here, we report a single-step synthesis of size-controlled and monodisperse, facetted γ-Al₂O₃ nanocrystals in an inductively coupled nonthermal plasma reactor using trimethylaluminum and oxygen as precursors. Under optimized conditions, we observed phase-pure, cuboctahedral γ-Al₂O₃ nanocrystals with defined surface facets. Nuclear magnetic resonance studies revealed that nanocrystal surfaces are populated with AlO₆, AlO₅ and AlO₄ units with clusters of hydroxyl groups. Nanocrystal size tuning was achieved by varying the total reactor pressure yielding particles as small as 3.5 nm, below the predicted thermodynamic stability limit for γ-Al₂O₃. Full article

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19 pages, 10429 KiB

Open AccessEditor’s ChoiceArticle

Cell-Biological Response and Sub-Toxic Inflammatory Effects of Titanium Dioxide Particles with Defined Polymorphic Phase, Size, and Shape

by Marina Breisch, Mateusz Olejnik, Kateryna Loza, Oleg Prymak, Nina Rosenkranz, Jürgen Bünger, Christina Sengstock, Manfred Köller, Götz Westphal and Matthias Epple

Nanomaterials 2023, 13(10), 1621; https://doi.org/10.3390/nano13101621 - 12 May 2023

Cited by 2 | Viewed by 1490

Abstract

Six types of titanium dioxide particles with defined size, shape, and crystal structure (polymorphic form) were prepared: nanorods (70 × 25 nm²), rutile sub-microrods (190 × 40 nm²), rutile microspheres (620 nm), anatase nanospheres (100 nm), anatase microspheres (510 [...] Read more.

Six types of titanium dioxide particles with defined size, shape, and crystal structure (polymorphic form) were prepared: nanorods (70 × 25 nm²), rutile sub-microrods (190 × 40 nm²), rutile microspheres (620 nm), anatase nanospheres (100 nm), anatase microspheres (510 nm), and amorphous titania microspheres (620 nm). All particles were characterized by scanning electron microscopy, X-ray powder diffraction, dynamic light scattering, infrared spectroscopy, and UV spectroscopy. The sub-toxic cell-biological response to these particles by NR8383 macrophages was assessed. All particle types were taken up well by the cells. The cytotoxicity and the induction of reactive oxygen species (ROS) were negligible for all particles up to a dose of 100 µg mL⁻¹, except for rutile microspheres which had a very rough surface in contrast to anatase and amorphous titania microspheres. The particle-induced cell migration assay (PICMA; based on chemotaxis) of all titanium dioxide particles was comparable to the effect of control silica nanoparticles (50 nm, uncoated, agglomerated) but did not show a trend with respect to particle size, shape, or crystal structure. The coating with carboxymethylcellulose (CMC) had no significant biological effect. However, the rough surface of rutile microspheres clearly induced pro-inflammatory cell reactions that were not predictable by the primary particle size alone. Full article

(This article belongs to the Special Issue Advances in Nano–Bio Interactions: Nanosafety and Nanotoxicology, Volume II)

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19 pages, 5084 KiB

Open AccessEditor’s ChoiceArticle

Green Nanoformulations of Polyvinylpyrrolidone-Capped Metal Nanoparticles: A Study at the Hybrid Interface with Biomimetic Cell Membranes and In Vitro Cell Models

by Alice Foti, Luana Calì, Salvatore Petralia and Cristina Satriano

Nanomaterials 2023, 13(10), 1624; https://doi.org/10.3390/nano13101624 - 12 May 2023

Cited by 4 | Viewed by 2017

Abstract

Noble metal nanoparticles (NP) with intrinsic antiangiogenic, antibacterial, and anti-inflammatory properties have great potential as potent chemotherapeutics, due to their unique features, including plasmonic properties for application in photothermal therapy, and their capability to slow down the migration/invasion speed of cancer cells and [...] Read more.

Noble metal nanoparticles (NP) with intrinsic antiangiogenic, antibacterial, and anti-inflammatory properties have great potential as potent chemotherapeutics, due to their unique features, including plasmonic properties for application in photothermal therapy, and their capability to slow down the migration/invasion speed of cancer cells and then suppress metastasis. In this work, gold (Au), silver (Ag), and palladium (Pd) NP were synthesized by a green redox chemistry method with the reduction of the metal salt precursor with glucose in the presence of polyvinylpyrrolidone (PVP) as stabilizing and capping agent. The physicochemical properties of the PVP-capped NP were investigated by UV-visible (UV-vis) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopies, dynamic light scattering (DLS), and atomic force microscopy (AFM), to scrutinize the optical features and the interface between the metal surface and the capping polymer, the hydrodynamic size, and the morphology, respectively. Biophysical studies with model cell membranes were carried out by using laser scanning confocal microscopy (LSM) with fluorescence recovery after photobleaching (FRAP) and fluorescence resonance energy transfer (FRET) techniques. To this purpose, artificial cell membranes of supported lipid bilayers (SLBs) made with 1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphocholine (POPC) dye-labeled with 7-nitro-2-1,3-benzoxadiazol-4-yl (NBD, FRET donor) and/or lissamine rhodamine B sulfonyl (Rh, FRET acceptor) were prepared. Proof-of-work in vitro cellular experiments were carried out with prostate cancer cells (PC-3 line) in terms of cytotoxicity, cell migration (wound scratch assay), NP cellular uptake, and cytoskeleton actin perturbation. Full article

(This article belongs to the Special Issue Prospects of Bioinspired and Biomimetic Materials)

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18 pages, 1106 KiB

Open AccessEditor’s ChoiceReview

The Roles of Extracellular Vesicles in the Progression of Renal Cell Carcinoma and Their Potential for Future Clinical Application

by Masashi Takeda, Shusuke Akamatsu, Yuki Kita, Takayuki Goto and Takashi Kobayashi

Nanomaterials 2023, 13(10), 1611; https://doi.org/10.3390/nano13101611 - 11 May 2023

Cited by 2 | Viewed by 2657

Abstract

Renal cell carcinoma (RCC) is the most common type of kidney cancer and is thought to originate from renal tubular epithelial cells. Extracellular vesicles (EVs) are nanosized lipid bilayer vesicles that are secreted into extracellular spaces by nearly all cell types, including cancer [...] Read more.

Renal cell carcinoma (RCC) is the most common type of kidney cancer and is thought to originate from renal tubular epithelial cells. Extracellular vesicles (EVs) are nanosized lipid bilayer vesicles that are secreted into extracellular spaces by nearly all cell types, including cancer cells and non-cancerous cells. EVs are involved in multiple steps of RCC progression, such as local invasion, host immune modulation, drug resistance, and metastasis. Therefore, EVs secreted from RCC are attracting rapidly increasing attention from researchers. In this review, we highlight the mechanism by which RCC-derived EVs lead to disease progression as well as the potential and challenges related to the clinical implications of EV-based diagnostics and therapeutics. Full article

(This article belongs to the Special Issue Applications of Nanotechnology in Medical Examination and Therapy)

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20 pages, 8465 KiB

Open AccessEditor’s ChoiceArticle

Zinc (Zn) Doping by Hydrothermal and Alkaline Heat-Treatment Methods on Titania Nanotube Arrays for Enhanced Antibacterial Activity

by Abhishek Bhattacharjee, Emma Goodall, Bruno Leandro Pereira, Paulo Soares and Ketul C. Popat

Nanomaterials 2023, 13(10), 1606; https://doi.org/10.3390/nano13101606 - 10 May 2023

Cited by 5 | Viewed by 2508

Abstract

Titanium (Ti) is a popular biomaterial for orthopedic implant applications due to its superior mechanical properties such as corrosion resistance and low modulus of elasticity. However, around 10% of these implants fail annually due to bacterial infection and poor osseointegration, resulting in severe [...] Read more.

Titanium (Ti) is a popular biomaterial for orthopedic implant applications due to its superior mechanical properties such as corrosion resistance and low modulus of elasticity. However, around 10% of these implants fail annually due to bacterial infection and poor osseointegration, resulting in severe pain and suffering for the patients. To improve their performance, nanoscale surface modification approaches and doping of trace elements on the surfaces can be utilized which may help in improving cell adhesion for better osseointegration while reducing bacterial infection. In this work, at first, titania (TiO₂) nanotube arrays (NT) were fabricated on commercially available pure Ti surfaces via anodization. Then zinc (Zn) doping was conducted following two distinct methods: hydrothermal and alkaline heat treatment. Scanning electron microscopic (SEM) images of the prepared surfaces revealed unique surface morphologies, while energy dispersive X-ray spectroscopy (EDS) revealed Zn distribution on the surfaces. Contact angle measurements indicated that NT surfaces were superhydrophilic. X-ray photoelectron spectroscopy (XPS) provided the relative amount of Zn on the surfaces and indicated that hydrothermally treated surfaces had more Zn compared to the alkaline heat-treated surfaces. X-ray crystallography (XRD) and nanoindentation techniques provided the crystal structure and mechanical properties of the surfaces. While testing with adipose-derived stem cells (ADSC), the surfaces showed no apparent cytotoxicity to the cells. Finally, bacteria adhesion and morphology were evaluated on the surfaces after 6 h and 24 h of incubation. From the results, it was confirmed that NT surfaces doped with Zn drastically reduced bacteria adhesion compared to the Ti control. Zn-doped NT surfaces thus offer a potential platform for orthopedic implant application. Full article

(This article belongs to the Special Issue Green/Sustainable Synthesis of Nanomaterials: Theranostics, Immunomodulation and Environmental Applications)

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15 pages, 4822 KiB

Open AccessEditor’s ChoiceArticle

Selective Catalytic Epoxidation–Hydration of α-Pinene with Hydrogen Peroxide to Sobrerol by Durable Ammonium Phosphotungstate Immobilized on Imidazolized Activated Carbon

by Min Zheng, Xiangzhou Li, Youyi Xun, Jianhua Wang and Dulin Yin

Nanomaterials 2023, 13(9), 1554; https://doi.org/10.3390/nano13091554 - 5 May 2023

Cited by 2 | Viewed by 1671

Abstract

It is presented that the activated carbon was carboxylated with hydrogen peroxide and then acylated with 2-methylimidazole to prepare the porous carbon support with a surface imidazolated modification. Through the adsorption of phosphotungstic acid on the fundamental site of an imidazolyl group and [...] Read more.

It is presented that the activated carbon was carboxylated with hydrogen peroxide and then acylated with 2-methylimidazole to prepare the porous carbon support with a surface imidazolated modification. Through the adsorption of phosphotungstic acid on the fundamental site of an imidazolyl group and then adjusting the acid strength with the ammonia molecule, a catalytic carbon material immobilized with ammonium phosphotungstate (AC-COIMO-NH₄PW) was obtained, which was used to catalyze a one-pot reaction of convenient α-pinene and hydrogen peroxide to sobrerol. The bifunctional active site originated from the dual property of ammonium phosphotungstate, as the oxidant and acid presenting a cooperatively catalytic performance, which effectively catalyzes the tandem epoxidation–isomerization–hydration of α-pinene to sobrerol, in which the solvent effect of catalysis simultaneously exists. The sobrerol selectivity was significantly improved after the acid strength weakening by ammonia. Monomolecular chemical bonding and anchoring of ammonium phosphotungstate at the basic site prevented the loss of the active catalytic species, and the recovered catalyst showed excellent catalytic stability in reuse. Using acetonitrile as the solvent at 40 °C for 4 h, the conversion of α-pinene could reach 90.6%, and the selectivity of sobrerol was 40.5%. The results of five cycles show that the catalyst presents excellent stability due to the tight immobilization of ammonium phosphotungstate bonding on the imidazolized activated carbon, based on which a catalytic-cycle mechanism is proposed for the tandem reaction. Full article

(This article belongs to the Special Issue Advanced Carbon Chemistry and Its Applications)

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15 pages, 3609 KiB

Open AccessEditor’s ChoiceArticle

Increasing the Stability of Isolated and Dense High-Aspect-Ratio Nanopillars Fabricated Using UV-Nanoimprint Lithography

by Michael J. Haslinger, Oliver S. Maier, Markus Pribyl, Philipp Taus, Sonja Kopp, Heinz D. Wanzenboeck, Kurt Hingerl, Michael M. Muehlberger and Elena Guillén

Nanomaterials 2023, 13(9), 1556; https://doi.org/10.3390/nano13091556 - 5 May 2023

Cited by 3 | Viewed by 2396

Abstract

Structural anti-reflective coating and bactericidal surfaces, as well as many other effects, rely on high-aspect-ratio (HAR) micro- and nanostructures, and thus, are of great interest for a wide range of applications. To date, there is no widespread fabrication of dense or isolated HAR [...] Read more.

Structural anti-reflective coating and bactericidal surfaces, as well as many other effects, rely on high-aspect-ratio (HAR) micro- and nanostructures, and thus, are of great interest for a wide range of applications. To date, there is no widespread fabrication of dense or isolated HAR nanopillars based on UV nanoimprint lithography (UV-NIL). In addition, little research on fabricating isolated HAR nanopillars via UV-NIL exists. In this work, we investigated the mastering and replication of HAR nanopillars with the smallest possible diameters for dense and isolated arrangements. For this purpose, a UV-based nanoimprint lithography process was developed. Stability investigations with capillary forces were performed and compared with simulations. Finally, strategies were developed in order to increase the stability of imprinted nanopillars or to convert them into nanoelectrodes. We present UV-NIL replication of pillars with aspect ratios reaching up to 15 with tip diameters down to 35 nm for the first time. We show that the stability could be increased by a factor of 58 when coating them with a 20 nm gold layer and by a factor of 164 when adding an additional 20 nm thick layer of SiN. The coating of the imprints significantly improved the stability of the nanopillars, thus making them interesting for a wide range of applications. Full article

(This article belongs to the Special Issue Advance in Nanoimprint Technology)

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10 pages, 2496 KiB

Open AccessEditor’s ChoiceArticle

Microencapsulation of Lead-Halide Perovskites in an Oil-in-Fluorine Emulsion for Cell Imaging

by Jia-Xin Wang, Chang Liu, Hao Huang, Rui He, Shengyong Geng and Xue-Feng Yu

Nanomaterials 2023, 13(9), 1540; https://doi.org/10.3390/nano13091540 - 4 May 2023

Cited by 1 | Viewed by 1544

Abstract

The superior optical properties of lead-halide perovskites (LHPs) inspired significant research in cell imaging applications; many encapsulating processes have improved perovskite stabilities with comparable biosafety. Herein, facile solvent evaporation encapsulation based on an oil-in-fluorine emulsion for aqueous-stable and extremely nontoxic LHP microcapsules is [...] Read more.

The superior optical properties of lead-halide perovskites (LHPs) inspired significant research in cell imaging applications; many encapsulating processes have improved perovskite stabilities with comparable biosafety. Herein, facile solvent evaporation encapsulation based on an oil-in-fluorine emulsion for aqueous-stable and extremely nontoxic LHP microcapsules is described. Perfluorooctane dispersed the emulsifier fluorocarbon surfactant to form a continuous fluorine phase, while LHPs and polymethylmethacrylate (PMMA) were dispersed in 1,2-dichloroethane, then emulsified in the fluorine phase to form an oil-in-fluorine emulsion. CsPbBr₃ microcapsules with a dense PMMA shell that protect fragile CsPbBr₃ from the external environment and inhibit lead ion release were obtained after solvent evaporation. The CsPbBr₃ microcapsules not only retained 91% of fluorescence intensity after exposure to water for 30 d but also possess extremely low cytotoxicity for MCF-7 cells. After exposure to 2 mg/mL of CsPbBr₃ microcapsules for 48 h, the cell viability remained >90%. The intracellular uptake of CsPbBr₃ microcapsules indicates its potential use in cell imaging. Full article

(This article belongs to the Topic Functional Surface Modifications of Nanostructures)

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15 pages, 3965 KiB

Open AccessEditor’s ChoiceArticle

Fabrication and Characterization of Hybrid Films Based on NiFe₂O₄ Nanoparticles in a Polymeric Matrix for Applications in Organic Electronics

by María Elena Sánchez Vergara, María José Agraz Rentería, América R. Vázquez-Olmos, Karen L. Rincón-Granados, José Ramón Álvarez Bada and Roberto Y. Sato-Berrú

Nanomaterials 2023, 13(9), 1525; https://doi.org/10.3390/nano13091525 - 30 Apr 2023

Viewed by 2098

Abstract

Hybrid films for applications in organic electronics from NiFe₂O₄ nanoparticles (NPs) in poly(3,4 ethylene dioxythiophene), poly(4-styrenesulfonate) (PEDOT:PSS), and poly(methyl methacrylate) (PMMA) were fabricated by the spin-coating technique. The films were characterized by infrared spectroscopy, atomic force microscopy, scanning electron microscopy, [...] Read more.

Hybrid films for applications in organic electronics from NiFe₂O₄ nanoparticles (NPs) in poly(3,4 ethylene dioxythiophene), poly(4-styrenesulfonate) (PEDOT:PSS), and poly(methyl methacrylate) (PMMA) were fabricated by the spin-coating technique. The films were characterized by infrared spectroscopy, atomic force microscopy, scanning electron microscopy, and energy-dispersive spectroscopy to subsequently determine their optical parameters. The electronic transport of the hybrid films was determined in bulk heterojunction devices. The presence of NiFe₂O₄ NPs reinforces mechanical properties and increases transmittance in the hybrid films; the PEDOT:PSS-NiFe₂O₄ NPs film is the one that has a maximum stress of 28 MPa and a Knoop hardness of 0.103, while the PMMA-NiFe₂O₄ NPs film has the highest transmittance of (87%). The Tauc band gap is in the range of 3.78–3.9 eV, and the Urbach energy is in the range of 0.24–0.33 eV. Regarding electrical behavior, the main effect is exerted by the matrix, although the current carried is of the same order of magnitude for the two devices: glass/ITO/polymer-NiFe₂O₄ NPs/Ag. NiFe₂O₄ NPs enhance the mechanical, optical, and electrical behavior of the hybrid films and can be used as semi-transparent anodes and as active layers. Full article

(This article belongs to the Special Issue Functional Nanomaterials for Flexible Electronics)

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30 pages, 3770 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Development of Two-Dimensional Functional Nanomaterials for Biosensor Applications: Opportunities, Challenges, and Future Prospects

by Shamsa Kizhepat, Akash S. Rasal, Jia-Yaw Chang and Hui-Fen Wu

Nanomaterials 2023, 13(9), 1520; https://doi.org/10.3390/nano13091520 - 29 Apr 2023

Cited by 13 | Viewed by 3381

Abstract

New possibilities for the development of biosensors that are ready to be implemented in the field have emerged thanks to the recent progress of functional nanomaterials and the careful engineering of nanostructures. Two-dimensional (2D) nanomaterials have exceptional physical, chemical, highly anisotropic, chemically active, [...] Read more.

New possibilities for the development of biosensors that are ready to be implemented in the field have emerged thanks to the recent progress of functional nanomaterials and the careful engineering of nanostructures. Two-dimensional (2D) nanomaterials have exceptional physical, chemical, highly anisotropic, chemically active, and mechanical capabilities due to their ultra-thin structures. The diversity of the high surface area, layered topologies, and porosity found in 2D nanomaterials makes them amenable to being engineered with surface characteristics that make it possible for targeted identification. By integrating the distinctive features of several varieties of nanostructures and employing them as scaffolds for bimolecular assemblies, biosensing platforms with improved reliability, selectivity, and sensitivity for the identification of a plethora of analytes can be developed. In this review, we compile a number of approaches to using 2D nanomaterials for biomolecule detection. Subsequently, we summarize the advantages and disadvantages of using 2D nanomaterials in biosensing. Finally, both the opportunities and the challenges that exist within this potentially fruitful subject are discussed. This review will assist readers in understanding the synthesis of 2D nanomaterials, their alteration by enzymes and composite materials, and the implementation of 2D material-based biosensors for efficient bioanalysis and disease diagnosis. Full article

(This article belongs to the Topic Advanced Nanomaterials for Sensing Applications)

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16 pages, 3588 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Hybrid Nanomaterial of Graphene Oxide Quantum Dots with Multi-Walled Carbon Nanotubes for Simultaneous Voltammetric Determination of Four DNA Bases

by Qusai Hassan, Chevon Riley, Meissam Noroozifar and Kagan Kerman

Nanomaterials 2023, 13(9), 1509; https://doi.org/10.3390/nano13091509 - 29 Apr 2023

Cited by 1 | Viewed by 1967

Abstract

In this proof-of-concept study, a novel hybrid nanomaterial-based electrochemical sensor was developed for the simultaneous detection of four DNA bases. For the modification of the working electrode surface, graphene oxide quantum dots (GOQDs) were synthesized using a solvothermal method. GOQDs were then used [...] Read more.

In this proof-of-concept study, a novel hybrid nanomaterial-based electrochemical sensor was developed for the simultaneous detection of four DNA bases. For the modification of the working electrode surface, graphene oxide quantum dots (GOQDs) were synthesized using a solvothermal method. GOQDs were then used for the preparation of a hybrid nanomaterial with multi-walled carbon nanotubes (GOQD-MWCNT) using a solvothermal technique for the first time. Transmission electron microscopy (TEM) was used to characterize the GOQDs-MWCNTs. A glassy carbon electrode (GCE) was modified with the GOQDs-MWCNTs using Nafion™ to prepare a GOQD-MWCNT/GCE for the simultaneous determination of four DNA bases in phosphate buffer solution (PBS, pH 7.0) using differential pulse voltammetry (DPV). The calibration plots were linear up to 50, 50, 500, and 500 µM with a limit of detection at 0.44, 0.2, 1.6, and 5.6 µM for guanine (G), adenine (A), thymine (T) and cytosine (C), respectively. The hybrid-modified sensor was used for the determination of G, A, T, and C spiked in the artificial saliva samples with the recovery values ranging from 95.9 to 106.8%. This novel hybrid-modified electrochemical sensor provides a promising platform for the future development of a device for cost-effective and efficient simultaneous detection of DNA bases in real biological and environmental samples. Full article

(This article belongs to the Topic Fabrication of Hybrid Materials for Catalysis)

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30 pages, 4515 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Recent Advances in ZnO Nanomaterial-Mediated Biological Applications and Action Mechanisms

by Jiani Xie, Huilun Li, Tairan Zhang, Bokai Song, Xinhui Wang and Zhanjun Gu

Nanomaterials 2023, 13(9), 1500; https://doi.org/10.3390/nano13091500 - 27 Apr 2023

Cited by 27 | Viewed by 3278

Abstract

In recent years, with the deepening research, metal zinc oxide (ZnO) nanomaterials have become a popular research object in the biological field, particularly in biomedicine and food safety, which is attributed to their unique physicochemical properties such as high surface area and volume [...] Read more.

In recent years, with the deepening research, metal zinc oxide (ZnO) nanomaterials have become a popular research object in the biological field, particularly in biomedicine and food safety, which is attributed to their unique physicochemical properties such as high surface area and volume ratio, luminescence effect, surface characteristics and biological activities. Herein, this review provides a detailed overview of the ZnO nanomaterial-mediated biological applications that involve anti-bacterial, anti-tumor, anti-inflammation, skin care, biological imaging and food packaging applications. Importantly, the corresponding action mechanisms of ZnO nanomaterials are pointed. Additionally, the structure and structure-dependent physicochemical properties, the common synthesis methods and the biosafety of ZnO nanoparticles are revealed in brief. Finally, the significance and future challenges of ZnO nanomaterial applications are concluded. Full article

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13 pages, 6280 KiB

Open AccessEditor’s ChoiceArticle

The Influence of the Size of BN NSs on Silkworm Development and Tissue Microstructure

by Vivian Andoh, Haiyan Liu, Liang Chen, Lin Ma and Keping Chen

Nanomaterials 2023, 13(9), 1502; https://doi.org/10.3390/nano13091502 - 27 Apr 2023

Viewed by 1605

Abstract

Boron nitride nanosheets (BN NSs) have emerged as promising materials in a wide range of biomedical applications. Despite the extensive studies on these bio-nano interfacial systems, one critical concern is their toxicity, which is affected by a variety of factors, including size. This [...] Read more.

Boron nitride nanosheets (BN NSs) have emerged as promising materials in a wide range of biomedical applications. Despite the extensive studies on these bio-nano interfacial systems, one critical concern is their toxicity, which is affected by a variety of factors, including size. This study aimed at assessing the relationship between BN NSs size and toxicity. Two silkworm strains (qiufeng × baiyu and Nistari 7019) were used as model organisms to investigate the effect of different sizes of BN NSs (BN NSs-1, thickness of 41.5 nm and diameter of 270.7 nm; BN NSs-2, thickness of 48.2 nm and diameter of 562.2 nm) on silkworm mortality, growth, cocoon weight, and tissue microstructure. The findings show that exposure to BN NSs in this work has no lethal adverse effects on silkworm growth or tissue microstructure. BN NSs have a higher effect on the growth rate of qiufeng × baiyu compared to Nistari 7019, demonstrating that the same treatment does not favorably affect the Nistari 7019 strain, as there is no significant increase in cocoon weight. Overall, the study suggests that the sizes of BN NSs employed in this study are relatively safe and have less negative impact on silkworms. This offers significant insights into the effect of BN NSs size, a crucial factor to consider for their safe use in biomedical applications. Full article

(This article belongs to the Special Issue Ecotoxicity Assessment of Nanomaterials: Latest Advances and Prospects)

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13 pages, 4630 KiB

Open AccessEditor’s ChoiceArticle

Reconstruction-Induced φ₀ Josephson Effect in Quantum Spin Hall Constrictions

by Lucia Vigliotti, Fabio Cavaliere, Giacomo Passetti, Maura Sassetti and Niccolò Traverso Ziani

Nanomaterials 2023, 13(9), 1497; https://doi.org/10.3390/nano13091497 - 27 Apr 2023

Cited by 7 | Viewed by 1840

Abstract

The simultaneous breaking of time-reversal and inversion symmetry, in connection to superconductivity, leads to transport properties with disrupting scientific and technological potential. Indeed, the anomalous Josephson effect and the superconducting-diode effect hold promises to enlarge the technological applications of superconductors and nanostructures in [...] Read more.

The simultaneous breaking of time-reversal and inversion symmetry, in connection to superconductivity, leads to transport properties with disrupting scientific and technological potential. Indeed, the anomalous Josephson effect and the superconducting-diode effect hold promises to enlarge the technological applications of superconductors and nanostructures in general. In this context, the system we theoretically analyze is a Josephson junction (JJ) with coupled reconstructed topological channels as a link; such channels are at the edges of a two-dimensional topological insulator (2DTI). We find a robust

φ_{0}

Josephson effect without requiring the presence of external magnetic fields. Our results, which rely on a fully analytical analysis, are substantiated by means of symmetry arguments: Our system breaks both time-reversal symmetry and inversion symmetry. Moreover, the anomalous current increases as a function of temperature. We interpret this surprising temperature dependence by means of simple qualitative arguments based on Fermi’s golden rule. Full article

(This article belongs to the Special Issue Recent Advances in Nanowires and Superconductors)

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22 pages, 6200 KiB

Open AccessEditor’s ChoiceArticle

Ultra-Sensitive and Fast Humidity Sensors Based on Direct Laser-Scribed Graphene Oxide/Carbon Nanotubes Composites

by Ammar Al-Hamry, Tianqi Lu, Haoran Chen, Anurag Adiraju, Salem Nasraoui, Amina Brahem, Danica Bajuk-Bogdanović, Saddam Weheabby, Igor A. Pašti and Olfa Kanoun

Nanomaterials 2023, 13(9), 1473; https://doi.org/10.3390/nano13091473 - 26 Apr 2023

Cited by 10 | Viewed by 2689

Abstract

In this paper, the relative humidity sensor properties of graphene oxide (GO) and graphene oxide/multiwalled nanotubes (GO/MWNTs) composites have been investigated. Composite sensors were fabricated by direct laser scribing and characterized using UV-vis-NIR, Raman, Fourier transform infrared, and X-ray photoemission spectroscopies, electron scanning [...] Read more.

In this paper, the relative humidity sensor properties of graphene oxide (GO) and graphene oxide/multiwalled nanotubes (GO/MWNTs) composites have been investigated. Composite sensors were fabricated by direct laser scribing and characterized using UV-vis-NIR, Raman, Fourier transform infrared, and X-ray photoemission spectroscopies, electron scanning microscopy coupled with energy-dispersive X-ray analysis, and impedance spectroscopy (IS). These methods confirm the composite homogeneity and laser reduction of GO/MWNT with dominant GO characteristics, while ISresults analysis reveals the circuit model for rGO-GO-rGO structure and the effect of MWNT on the sensor properties. Although direct laser scribing of GO-based humidity sensor shows an outstanding response (|ΔZ|/|Z| up to 638,800%), a lack of stability and repeatability has been observed. GO/MWNT-based humidity sensors are more conductive than GO sensors and relatively less sensitive (|ΔZ|/|Z| = 163,000%). However, they are more stable in harsh humid conditions, repeatable, and reproducible even after several years of shelf-life. In addition, they have fast response/recovery times of 10.7 s and 9.3 s and an ultra-fast response time of 61 ms when abrupt humidification/dehumidification is applied by respiration. All carbon-based sensors’ overall properties confirm the advantage of introducing the GO/MWNT hybrid and laser direct writing to produce stable structures and sensors. Full article

(This article belongs to the Special Issue Laser-Matter Interaction for Nanostructuration and Characterization: From Fundamentals to Sensing and Energy Applications)

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14 pages, 3461 KiB

Open AccessEditor’s ChoiceArticle

The Mechanism of Manganese Ferrite Nanomaterials Promoting Drought Resistance in Rice

by Le Yue, Budiao Xie, Xuesong Cao, Feiran Chen, Chuanxi Wang, Zhenggao Xiao, Liya Jiao and Zhenyu Wang

Nanomaterials 2023, 13(9), 1484; https://doi.org/10.3390/nano13091484 - 26 Apr 2023

Cited by 1 | Viewed by 1706

Abstract

Strategies to reduce the risk of drought damage are urgently needed as intensified climate change threatens agricultural production. One potential strategy was using nanomaterials (NMs) to enhance plant resistance by regulating various physiological and biochemical processes. In the present study, 10 mg kg [...] Read more.

Strategies to reduce the risk of drought damage are urgently needed as intensified climate change threatens agricultural production. One potential strategy was using nanomaterials (NMs) to enhance plant resistance by regulating various physiological and biochemical processes. In the present study, 10 mg kg⁻¹ manganese ferrite (MnFe₂O₄) NMs had the optimal enhancement to elevate the levels of biomass, photosynthesis, nutrient elements, and polysaccharide in rice by 10.9–525.0%, respectively, under drought stress. The MnFe₂O₄ NMs were internalized by rice plants, which provided the possibility for rice to better cope with drought. Furthermore, as compared with drought control and equivalent ion control, the introduction of MnFe₂O₄ NMs into the roots significantly upregulated the drought-sensing gene CLE25 (29.4%) and the receptor gene NCED3 (59.9%). This activation stimulated downstream abscisic acid, proline, malondialdehyde, and wax biosynthesis by 23.3%, 38.9%, 7.2%, and 26.2%, respectively. In addition, 10 mg·kg⁻¹ MnFe₂O₄ NMs significantly upregulated the relative expressions of OR1, AUX2, AUX3, PIN1a, and PIN2, and increased IAA content significantly, resulting in an enlarged root angle and a deeper and denser root to help the plant withstand drought stresses. The nutritional quality of rice grains was also improved. Our study provides crucial insight for developing nano-enabled strategies to improve crop productivity and resilience to climate change. Full article

(This article belongs to the Special Issue Advanced Nanomaterials and Nanotechnology in Agricultural Applications)

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14 pages, 2494 KiB

Open AccessEditor’s ChoiceArticle

Enhanced Spectral Response of ZnO-Nanorod-Array-Based Ultraviolet Photodetectors by Alloying Non-Isovalent Cu–O with CuAlO₂ P-Type Layer

by Yuchen Long, Ziling Zhang, Xiutao Yang, Yang Liu, Guangcan Luo, Jingquan Zhang and Wei Li

Nanomaterials 2023, 13(9), 1472; https://doi.org/10.3390/nano13091472 - 26 Apr 2023

Cited by 5 | Viewed by 1621

Abstract

CuAlO₂ was synthesized by a hydrothermal method, in which the Cu–O dimers were incorporated by simply altering the ratio of the reactants and the temperature. The incorporation process increases the grain size in CuAlO₂, and modulates the work function and [...] Read more.

CuAlO₂ was synthesized by a hydrothermal method, in which the Cu–O dimers were incorporated by simply altering the ratio of the reactants and the temperature. The incorporation process increases the grain size in CuAlO₂, and modulates the work function and binding energies for CuAlO₂ due to the partial substitution of Cu⁺ 3d¹⁰ with Cu²⁺ 3d⁹ orbitals in the valence band maximum by alloying non-isovalent Cu–O with a CuAlO₂ host. Based on the ZnO nanorod arrays (NRs) ultraviolet photodetector, CuAlO₂/Cu–O fabricated by the low-cost drop-coating method was used as the p-type hole transport layer. The incorporation of the Cu–O clusters into CuAlO₂ lattice to enhance the conductivity of CuAlO₂ is an effective way for improving ZnO NRs/CuAlO₂ device performance. The photodetectors exhibit significant diode behavior, with a rectification ratio approaching 30 at ±1 V, and a dark saturation current density 0.81 mA cm⁻². The responsivity of the ZnO-NRs-based UV photodetector increases from 13.2 to 91.3 mA/W at 0 V bias, with an increase in the detectivity from 2.35 × 10¹⁰ to 1.71 × 10¹¹ Jones. Furthermore, the ZnO NRs/[CuAlO₂/Cu–O] photodetector exhibits a maximum responsivity of 5002 mA/W at 1.5 V bias under 375 nm UV illumination. Full article

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11 pages, 4760 KiB

Open AccessEditor’s ChoiceArticle

Chitin-Derived Nitrogen-Doped Carbon Nanopaper with Subwavelength Nanoporous Structures for Solar Thermal Heating

by Thanakorn Yeamsuksawat, Luting Zhu, Takaaki Kasuga, Masaya Nogi and Hirotaka Koga

Nanomaterials 2023, 13(9), 1480; https://doi.org/10.3390/nano13091480 - 26 Apr 2023

Cited by 4 | Viewed by 2557

Abstract

Sustainable biomass-derived carbons have attracted research interest because of their ability to effectively absorb and convert solar light to thermal energy, a phenomenon known as solar thermal heating. Although their carbon-based molecular and nanoporous structures should be customized to achieve enhanced solar thermal [...] Read more.

Sustainable biomass-derived carbons have attracted research interest because of their ability to effectively absorb and convert solar light to thermal energy, a phenomenon known as solar thermal heating. Although their carbon-based molecular and nanoporous structures should be customized to achieve enhanced solar thermal heating performance, such customization has insufficiently progressed. In this study, we transformed a chitin nanofiber/water dispersion into paper, referred to as chitin nanopaper, with subwavelength nanoporous structures by spatially controlled drying, followed by temperature-controlled carbonization without any pretreatment to customize the carbon-based molecular structures. The optimal carbonization temperature for enhancing the solar absorption and solar thermal heating performance of the chitin nanopaper was determined to be 400 °C. Furthermore, we observed that the nitrogen component, which afforded nitrogen-doped carbon structures, and the high morphological stability of chitin nanofibers against carbonization, which maintained subwavelength nanoporous structures even after carbonization, contributed to the improved solar absorption of the carbonized chitin nanopaper. The carbonized chitin nanopaper exhibited a higher solar thermal heating performance than the carbonized cellulose nanopaper and commercial nanocarbon materials, thus demonstrating significant potential as an excellent solar thermal material. Full article

(This article belongs to the Special Issue Synthesis and Application of Biomass-Derived Carbon-Based Nanomaterials)

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15 pages, 4047 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Targeting of Tomato Bushy Stunt Virus with a Genetically Fused C-End Rule Peptide

by Luca Marchetti, Lorena Simon-Gracia, Chiara Lico, Mariateresa Mancuso, Selene Baschieri, Luca Santi and Tambet Teesalu

Nanomaterials 2023, 13(8), 1428; https://doi.org/10.3390/nano13081428 - 21 Apr 2023

Cited by 1 | Viewed by 2113

Abstract

Homing peptides are widely used to improve the delivery of drugs, imaging agents, and nanoparticles (NPs) to their target sites. Plant virus-based particles represent an emerging class of structurally diverse nanocarriers that are biocompatible, biodegradable, safe, and cost-effective. Similar to synthetic NPs, these [...] Read more.

Homing peptides are widely used to improve the delivery of drugs, imaging agents, and nanoparticles (NPs) to their target sites. Plant virus-based particles represent an emerging class of structurally diverse nanocarriers that are biocompatible, biodegradable, safe, and cost-effective. Similar to synthetic NPs, these particles can be loaded with imaging agents and/or drugs and functionalized with affinity ligands for targeted delivery. Here we report the development of a peptide-guided Tomato Bushy Stunt Virus (TBSV)-based nanocarrier platform for affinity targeting with the C-terminal C-end rule (CendR) peptide, RPARPAR (RPAR). Flow cytometry and confocal microscopy demonstrated that the TBSV-RPAR NPs bind specifically to and internalize in cells positive for the peptide receptor neuropilin-1 (NRP-1). TBSV-RPAR particles loaded with a widely used anticancer anthracycline, doxorubicin, showed selective cytotoxicity on NRP-1-expressing cells. Following systemic administration in mice, RPAR functionalization conferred TBSV particles the ability to accumulate in the lung tissue. Collectively, these studies show the feasibility of the CendR-targeted TBSV platform for the precision delivery of payloads. Full article

(This article belongs to the Special Issue Advances in Nanoscale Materials in Biomedicine)

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28 pages, 5923 KiB

Open AccessEditor’s ChoiceReview

A Review on the Applications of Natural Biodegradable Nano Polymers in Cardiac Tissue Engineering

by Rabia Aziz, Mariarosaria Falanga, Jelena Purenovic, Simona Mancini, Patrizia Lamberti and Michele Guida

Nanomaterials 2023, 13(8), 1374; https://doi.org/10.3390/nano13081374 - 15 Apr 2023

Cited by 5 | Viewed by 2578

Abstract

As cardiac diseases, which mostly result in heart failure, are increasing rapidly worldwide, heart transplantation seems the only solution for saving lives. However, this practice is not always possible due to several reasons, such as scarcity of donors, rejection of organs from recipient [...] Read more.

As cardiac diseases, which mostly result in heart failure, are increasing rapidly worldwide, heart transplantation seems the only solution for saving lives. However, this practice is not always possible due to several reasons, such as scarcity of donors, rejection of organs from recipient bodies, or costly medical procedures. In the framework of nanotechnology, nanomaterials greatly contribute to the development of these cardiovascular scaffolds as they provide an easy regeneration of the tissues. Currently, functional nanofibers can be used in the production of stem cells and in the regeneration of cells and tissues. The small size of nanomaterials, however, leads to changes in their chemical and physical characteristics that could alter their interaction and exposure to stem cells with cells and tissues. This article aims to review the naturally occurring biodegradable nanomaterials that are used in cardiovascular tissue engineering for the development of cardiac patches, vessels, and tissues. Moreover, this article also provides an overview of cell sources used for cardiac tissue engineering, explains the anatomy and physiology of the human heart, and explores the regeneration of cardiac cells and the nanofabrication approaches used in cardiac tissue engineering as well as scaffolds. Full article

(This article belongs to the Special Issue Advances in Natural and Bio-Inspired Nanoparticles for the Treatment of Cardiovascular Diseases)

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18 pages, 4631 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Magnetic Properties and Magnetocaloric Effect of Polycrystalline and Nano-Manganites Pr_0.65Sr_(0.35−x)Ca_xMnO₃ (x ≤ 0.3)

by Roman Atanasov, Dorin Ailenei, Rares Bortnic, Razvan Hirian, Gabriela Souca, Adam Szatmari, Lucian Barbu-Tudoran and Iosif Grigore Deac

Nanomaterials 2023, 13(8), 1373; https://doi.org/10.3390/nano13081373 - 14 Apr 2023

Cited by 6 | Viewed by 1656

Abstract

Here we report investigations of bulk and nano-sized Pr_0.65Sr_(0.35−x)Ca_xMnO₃ compounds (x ≤ 0.3). Solid-state reaction was implemented for polycrystalline compounds and a modified sol–gel method was used for nanocrystalline compounds. X-ray diffraction disclosed diminishing cell volume [...] Read more.

Here we report investigations of bulk and nano-sized Pr_0.65Sr_(0.35−x)Ca_xMnO₃ compounds (x ≤ 0.3). Solid-state reaction was implemented for polycrystalline compounds and a modified sol–gel method was used for nanocrystalline compounds. X-ray diffraction disclosed diminishing cell volume with increasing Ca substitution in Pbnm space group for all samples. Optical microscopy was used for bulk surface morphology and transmission electron microscopy was utilized for nano-sized samples. Iodometric titration showed oxygen deficiency for bulk compounds and oxygen excess for nano-sized particles. Measurements of resistivity of bulk samples revealed features at temperatures associated with grain boundary condition and with ferromagnetic (FM)/paramagnetic (PM) transition. All samples exhibited negative magnetoresistivity. Magnetic critical behavior analysis suggested the polycrystalline samples are governed by a tricritical mean field model while nanocrystalline samples are governed by a mean field model. Curie temperatures values lower with increasing Ca substitution from 295 K for the parent compound to 201 K for x = 0.2. Bulk compounds exhibit high entropy change, with the highest value of 9.21 J/kgK for x = 0.2. Magnetocaloric effect and the possibility of tuning the Curie temperature by Ca substitution of Sr make the investigated bulk polycrystalline compounds promising for application in magnetic refrigeration. Nano-sized samples possess wider effective entropy change temperature (ΔT_fwhm) and lower entropy changes of around 4 J/kgK which, however, puts in doubt their straightforward potential for applications as magnetocaloric materials. Full article

(This article belongs to the Special Issue Innovative Nanomaterial Properties and Applications in Chemistry, Physics, Medicine, or Environment)

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11 pages, 1334 KiB

Open AccessEditor’s ChoiceArticle

Nanoscale Clustering in an Additively Manufactured Zr-Based Metallic Glass Evaluated by Atom Probe Tomography

by Inga K. Goetz, Janis A. Sälker, Marcus Hans, Björgvin Hjörvarsson and Jochen M. Schneider

Nanomaterials 2023, 13(8), 1341; https://doi.org/10.3390/nano13081341 - 12 Apr 2023

Cited by 3 | Viewed by 1357

Abstract

Composition analysis at the nm-scale, marking the onset of clustering in bulk metallic glasses, can aid the understanding and further optimization of additive manufacturing processes. By atom probe tomography, it is challenging to differentiate nm-scale segregations from random fluctuations. This ambiguity is due [...] Read more.

Composition analysis at the nm-scale, marking the onset of clustering in bulk metallic glasses, can aid the understanding and further optimization of additive manufacturing processes. By atom probe tomography, it is challenging to differentiate nm-scale segregations from random fluctuations. This ambiguity is due to the limited spatial resolution and detection efficiency. Cu and Zr were selected as model systems since the spatial distributions of the isotopes therein constitute ideal solid solutions, as the mixing enthalpy is, by definition, zero. Close agreement is observed between the simulated and measured spatial distributions of the isotopes. Having established the signature of a random distribution of atoms, the elemental distribution in amorphous Zr_59.3Cu_28.8Al_10.4Nb_1.5 samples fabricated by laser powder bed fusion is analyzed. By comparison with the length scales of spatial isotope distributions, the probed volume of the bulk metallic glass shows a random distribution of all constitutional elements, and no evidence for clustering is observed. However, heat-treated metallic glass samples clearly exhibit elemental segregation which increases in size with annealing time. Segregations in Zr_59.3Cu_28.8Al_10.4Nb_1.5 > 1 nm can be observed and separated from random fluctuations, while accurate determination of segregations < 1 nm in size are limited by spatial resolution and detection efficiency. Full article

(This article belongs to the Section Nanocomposite Materials)

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40 pages, 6170 KiB

Open AccessEditor’s ChoiceReview

Iron Oxide@Mesoporous Silica Core-Shell Nanoparticles as Multimodal Platforms for Magnetic Resonance Imaging, Magnetic Hyperthermia, Near-Infrared Light Photothermia, and Drug Delivery

by Alexandre Adam and Damien Mertz

Nanomaterials 2023, 13(8), 1342; https://doi.org/10.3390/nano13081342 - 12 Apr 2023

Cited by 26 | Viewed by 5898

Abstract

The design of core-shell nanocomposites composed of an iron oxide core and a silica shell offers promising applications in the nanomedicine field, especially for developing efficient theranostic systems which may be useful for cancer treatments. This review article addresses the different ways to [...] Read more.

The design of core-shell nanocomposites composed of an iron oxide core and a silica shell offers promising applications in the nanomedicine field, especially for developing efficient theranostic systems which may be useful for cancer treatments. This review article addresses the different ways to build iron oxide@silica core-shell nanoparticles and it reviews their properties and developments for hyperthermia therapies (magnetically or light-induced), combined with drug delivery and MRI imaging. It also highlights the various challenges encountered, such as the issues associated with in vivo injection in terms of NP–cell interactions or the control of the heat dissipation from the core of the NP to the external environment at the macro or nanoscale. Full article

(This article belongs to the Special Issue Plasmonic and Magnetic Nanoparticles for Localized-Hyperthermia)

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