Nanomaterials

13 pages, 2861 KiB

Open AccessEditor’s ChoiceArticle

Highly Dispersed Pt-Incorporated Mesoporous Fe₂O₃ for Low-Level Sensing of Formaldehyde Gas

by Seung Jin Jeon, Kyung Hee Oh, Youngbo Choi, Ji Chan Park and Hyung Ju Park

Nanomaterials 2023, 13(4), 659; https://doi.org/10.3390/nano13040659 - 8 Feb 2023

Cited by 3 | Viewed by 2308

Highly dispersed Pt-incorporated mesoporous Fe₂O₃ (Pt/m-Fe₂O₃) of 4 μm size is prepared through a simple hydrothermal reaction and thermal decomposition procedures. Furthermore, the formaldehyde gas-sensing properties of Pt/m-Fe₂O₃ are investigated. Compared with our [...] Read more.

Highly dispersed Pt-incorporated mesoporous Fe₂O₃ (Pt/m-Fe₂O₃) of 4 μm size is prepared through a simple hydrothermal reaction and thermal decomposition procedures. Furthermore, the formaldehyde gas-sensing properties of Pt/m-Fe₂O₃ are investigated. Compared with our previous mesoporous Fe₂O₃-based gas sensors, a gas sensor based on 0.2% Pt/m-Fe₂O₃ shows improved gas response by over 90% in detecting low-level formaldehyde gas at 50 ppb concentration, an enhanced selectivity of formaldehyde gas, and a lower degradation of sensing performance in high-humidity environments. Additionally, the gas sensor exhibits similar properties as the previous sensor, such as operating temperature (275 °C) and long-term stability. The enhancement in formaldehyde gas-sensing performance is attributed to the attractive catalytic chemical sensitization of highly dispersed Pt nanoparticles in the mesoporous Fe₂O₃ microcube architecture. Full article

(This article belongs to the Section Nanoelectronics, Nanosensors and Devices)

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24 pages, 14607 KiB

Open AccessEditor’s ChoiceArticle

Mechanical Reinforcement of ABS with Optimized Nano Titanium Nitride Content for Material Extrusion 3D Printing

by Nectarios Vidakis, Panagiotis Mangelis, Markos Petousis, Nikolaos Mountakis, Vassilis Papadakis, Amalia Moutsopoulou and Dimitris Tsikritzis

Nanomaterials 2023, 13(4), 669; https://doi.org/10.3390/nano13040669 - 8 Feb 2023

Cited by 18 | Viewed by 2638

Abstract

Acrylonitrile Butadiene Styrene (ABS) nanocomposites were developed using Material Extrusion (MEX) Additive Manufacturing (AM) and Fused Filament Fabrication (FFF) methods. A range of mechanical tests was conducted on the produced 3D-printed structures to investigate the effect of Titanium Nitride (TiN) nanoparticles on the [...] Read more.

Acrylonitrile Butadiene Styrene (ABS) nanocomposites were developed using Material Extrusion (MEX) Additive Manufacturing (AM) and Fused Filament Fabrication (FFF) methods. A range of mechanical tests was conducted on the produced 3D-printed structures to investigate the effect of Titanium Nitride (TiN) nanoparticles on the mechanical response of thermoplastic polymers. Detailed morphological characterization of the produced filaments and 3D-printed specimens was carried out using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). High-magnification images revealed a direct impact of the TiN concentration on the surface characteristics of the nanocomposites, indicating a strong correlation with their mechanical performance. The chemical compositions of the raw and nanocomposite materials were thoroughly investigated by conducting Raman and Energy Dispersive Spectroscopy (EDS) measurements. Most of the mechanical properties were improved with the inclusion of TiN nanoparticles with a content of 6 wt. % to reach the optimum mechanical response overall. ABS/TiN 6 wt. % exhibits remarkable increases in flexural modulus of elasticity (42.3%) and toughness (54.0%) in comparison with pure ABS. The development of ABS/TiN nanocomposites with reinforced mechanical properties is a successful example that validates the feasibility and powerful abilities of MEX 3D printing in AM. Full article

(This article belongs to the Special Issue Nanostructured Ceramics in Modern Materials Science)

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17 pages, 5305 KiB

Open AccessEditor’s ChoiceArticle

Synthesis of Fe-TiO₂ and Cu-TiO₂ Based Materials by Olive Leaves Biotemplating—Application to Hydrogen Production from Glycerol Photoreforming

by Juan Martín-Gómez, Susana Reca-Expósito, Francisco J. López-Tenllado, Jesús Hidalgo-Carrillo, Alberto Marinas and Francisco J. Urbano

Nanomaterials 2023, 13(4), 664; https://doi.org/10.3390/nano13040664 - 8 Feb 2023

Cited by 1 | Viewed by 2020

Abstract

Hydrogen production is mainly based on the use of fossil fuels, but currently, many alternative routes are being developed, among which the photo-reforming of oxygenated organic compounds stands out. Recently, several studies have been carried out in order to develop new techniques to [...] Read more.

Hydrogen production is mainly based on the use of fossil fuels, but currently, many alternative routes are being developed, among which the photo-reforming of oxygenated organic compounds stands out. Recently, several studies have been carried out in order to develop new techniques to create bio-inspired TiO₂ structures. One of these is ‘biotemplating’, a process that replicates a biological system in an inorganic TiO₂-based structure. In this study, olive by-products—olive leaves—are valorized as a biotemplate for the synthesis of new Fe-TiO_2- and Cu-TiO₂-based photocatalysts with the aim of improving the replication of the leaf structure and enhancing hydrogen photoproduction. In conclusion, the incorporation of iron and copper decreases the band gap and increases the energetic disorder at the band edges. Moreover, it is verified by SEM and TEM that the metals are not found forming particles but are introduced into the formed TiO₂ structure. The accuracy of the internal and external structure replication is improved with the incorporation of Fe in the synthesis, while the incorporation of Cu substantially improves the production of hydrogen, which is multiplied 14 times under UV light and 6 times under sunlight, as compared to a pure TiO₂ structure. Full article

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22 pages, 2599 KiB

Open AccessEditor’s ChoiceReview

Luminescent Gold Nanoclusters for Bioimaging: Increasing the Ligand Complexity

by Dario Mordini, Alexandra Mavridi-Printezi, Arianna Menichetti, Andrea Cantelli, Xinke Li and Marco Montalti

Nanomaterials 2023, 13(4), 648; https://doi.org/10.3390/nano13040648 - 7 Feb 2023

Cited by 10 | Viewed by 3172

Abstract

Fluorescence, and more in general, photoluminescence (PL), presents important advantages for imaging with respect to other diagnostic techniques. In particular, detection methodologies exploiting fluorescence imaging are fast and versatile; make use of low-cost and simple instrumentations; and are taking advantage of newly developed [...] Read more.

Fluorescence, and more in general, photoluminescence (PL), presents important advantages for imaging with respect to other diagnostic techniques. In particular, detection methodologies exploiting fluorescence imaging are fast and versatile; make use of low-cost and simple instrumentations; and are taking advantage of newly developed powerful, low-cost, light-based electronic devices, such as light sources and cameras, used in huge market applications, such as civil illumination, computers, and cellular phones. Besides the aforementioned simplicity, fluorescence imaging offers a spatial and temporal resolution that can hardly be achieved with alternative methods. However, the two main limitations of fluorescence imaging for bio-application are still (i) the biological tissue transparency and autofluorescence and (ii) the biocompatibility of the contrast agents. Luminescent gold nanoclusters (AuNCs), if properly designed, combine high biocompatibility with PL in the near-infrared region (NIR), where the biological tissues exhibit higher transparency and negligible autofluorescence. However, the stabilization of these AuNCs requires the use of specific ligands that also affect their PL properties. The nature of the ligand plays a fundamental role in the development and sequential application of PL AuNCs as probes for bioimaging. Considering the importance of this, in this review, the most relevant and recent papers on AuNCs-based bioimaging are presented and discussed highlighting the different functionalities achieved by increasing the complexity of the ligand structure. Full article

(This article belongs to the Special Issue Nanobiotechnologies in Environment and Medicine)

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0 pages, 7762 KiB

Open AccessEditor’s ChoiceArticle

Performance of Cu/ZnO Nanosheets on Electrospun Al₂O₃ Nanofibers in CO₂ Catalytic Hydrogenation to Methanol and Dimethyl Ether

by Itzhak I. Maor, Svetlana Heyte, Oren Elishav, Meirav Mann-Lahav, Joelle Thuriot-Roukos, Sébastien Paul and Gideon S. Grader

Nanomaterials 2023, 13(4), 635; https://doi.org/10.3390/nano13040635 - 5 Feb 2023

Cited by 4 | Viewed by 4312

Abstract

The synthesis of methanol and dimethyl ether (DME) from carbon dioxide (CO₂) and green hydrogen (H₂) offers a sustainable pathway to convert CO₂ emissions into value-added products. This heterogeneous catalytic reaction often uses copper (Cu) catalysts due to [...] Read more.

The synthesis of methanol and dimethyl ether (DME) from carbon dioxide (CO₂) and green hydrogen (H₂) offers a sustainable pathway to convert CO₂ emissions into value-added products. This heterogeneous catalytic reaction often uses copper (Cu) catalysts due to their low cost compared with their noble metal analogs. Nevertheless, improving the activity and selectivity of these Cu catalysts for these products is highly desirable. In the present study, a new architecture of Cu- and Cu/Zn-based catalysts supported on electrospun alumina nanofibers were synthesized. The catalysts were tested under various reaction conditions using high-throughput equipment to highlight the role of the hierarchical fibrous structure on the reaction activity and selectivity. The Cu or Cu/ZnO formed a unique structure of nanosheets, covering the alumina fiber surface. This exceptional morphology provides a large surface area, up to ~300 m²/g, accessible for reaction. Maximal production of methanol (~1106 g_methanolKg_Cu⁻¹∙h⁻¹) and DME (760 g_DMEKg_Cu⁻¹∙h⁻¹) were obtained for catalysts containing 7% wt. Cu/Zn with a weight ratio of 2.3 Zn to Cu (at 300 °C, 50 bar). The promising results in CO₂ hydrogenation to methanol and DME obtained here point out the significant advantage of nanofiber-based catalysts in heterogeneous catalysis. Full article

(This article belongs to the Special Issue Nanocatalysts for Methanation Reaction)

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23 pages, 6785 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Synthesis and Anti-Melanoma Activity of L-Cysteine-Coated Iron Oxide Nanoparticles Loaded with Doxorubicin

by Luiza Izabela Toderascu, Livia Elena Sima, Stefana Orobeti, Paula Ecaterina Florian, Madalina Icriverzi, Valentin-Adrian Maraloiu, Cezar Comanescu, Nicusor Iacob, Victor Kuncser, Iulia Antohe, Gianina Popescu-Pelin, George Stanciu, Petre Ionita, Cristian N. Mihailescu and Gabriel Socol

Nanomaterials 2023, 13(4), 621; https://doi.org/10.3390/nano13040621 - 4 Feb 2023

Cited by 9 | Viewed by 3240

Abstract

In this study, we report on the synthesis of L-Cysteine (L-Cys)-coated magnetic iron oxide nanoparticles (NPs) loaded with doxorubicin (Dox). The Fe₃O₄-L-Cys-Dox NPs were extensively characterized for their compositional and morpho-structural features using EDS, SAED, XRD, FTIR and TEM. [...] Read more.

In this study, we report on the synthesis of L-Cysteine (L-Cys)-coated magnetic iron oxide nanoparticles (NPs) loaded with doxorubicin (Dox). The Fe₃O₄-L-Cys-Dox NPs were extensively characterized for their compositional and morpho-structural features using EDS, SAED, XRD, FTIR and TEM. XPS, Mӧssbauer spectroscopy and SQUID measurements were also performed to determine the electronic and magnetic properties of the Fe₃O₄-L-Cys-Dox nanoparticles. Moreover, by means of a FO-SPR sensor, we evidenced and confirmed the binding of Dox to L-Cys. Biological tests on mouse (B16F10) and human (A375) metastatic melanoma cells evidenced the internalization of magnetic nanoparticles delivering Dox. Half maximum inhibitory concentration IC50 values of Fe₃O₄-L-Cys-Dox were determined for both cell lines: 4.26 µg/mL for A375 and 2.74 µg/mL for B16F10, as compared to 60.74 and 98.75 µg/mL, respectively, for unloaded controls. Incubation of cells with Fe₃O₄-L-Cys-Dox modulated MAPK signaling pathway activity 3 h post-treatment and produced cell cycle arrest and increased apoptosis by 48 h. We show that within the first 2 h of incubation in physiological (pH = 7.4) media, ~10–15 µM Dox/h was released from a 200 µg/mL Fe₃O₄-L-Cys-Dox solution, as compared to double upon incubation in citrate solution (pH = 3), which resembles acidic environment conditions. Our results highlight the potential of Fe₃O₄-L-Cys-Dox NPs as efficient drug delivery vehicles in melanoma therapy. Full article

(This article belongs to the Special Issue Thin Films Based on Nanocomposites (2nd Edition))

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9 pages, 2398 KiB

Open AccessEditor’s ChoiceCommunication

Quasi-2D Mn₃Si₂Te₆ Nanosheet for Ultrafast Photonics

by Yan Lu, Zheng Zhou, Xuefen Kan, Zixin Yang, Haiqin Deng, Bin Liu, Tongtong Wang, Fangqi Liu, Xueyu Liu, Sicong Zhu, Qiang Yu and Jian Wu

Nanomaterials 2023, 13(3), 602; https://doi.org/10.3390/nano13030602 - 2 Feb 2023

Cited by 3 | Viewed by 2490

Abstract

The magnetic nanomaterial Mn₃Si₂Te₆ is a promising option for spin-dependent electronic and magneto-optoelectronic devices. However, its application in nonlinear optics remains fanciful. Here, we demonstrate a pulsed Er-doped fiber laser (EDFL) based on a novel quasi-2D Mn₃ [...] Read more.

The magnetic nanomaterial Mn₃Si₂Te₆ is a promising option for spin-dependent electronic and magneto-optoelectronic devices. However, its application in nonlinear optics remains fanciful. Here, we demonstrate a pulsed Er-doped fiber laser (EDFL) based on a novel quasi-2D Mn₃Si₂Te₆ saturable absorber (SA) with low pump power at 1.5 μm. The high-quality Mn₃Si₂Te₆ crystals were synthesized by the self-flux method, and the ultrathin Mn₃Si₂Te₆ nanoflakes were prepared by a simple mechanical exfoliation procedure. To the best of our knowledge, this is the first time laser pulses have been generated using quasi-2D Mn₃Si₂Te₆. A stable pulsed laser at 1562 nm with a low threshold pump power of 60 mW was produced by integrating the Mn₃Si₂Te₆ SA into an EDFL cavity. The maximum power of the output pulse is 783 μW. The repetition rate can vary from 24.16 to 44.44 kHz, with corresponding pulse durations of 5.64 to 3.41 µs. Our results indicate that the quasi-2D Mn₃Si₂Te₆ is a promising material for application in ultrafast photonics. Full article

(This article belongs to the Special Issue Advance in Nanophotonics)

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22 pages, 11167 KiB

Open AccessEditor’s ChoiceReview

Nanomaterials and Devices for Harvesting Ambient Electromagnetic Waves

by Mircea Dragoman, Martino Aldrigo, Adrian Dinescu, Dan Vasilache, Sergiu Iordanescu and Daniela Dragoman

Nanomaterials 2023, 13(3), 595; https://doi.org/10.3390/nano13030595 - 2 Feb 2023

Cited by 6 | Viewed by 2804

Abstract

This manuscript presents an overview of the implications of nanomaterials in harvesting ambient electromagnetic waves. We show that the most advanced electromagnetic harvesting devices are based on oxides with a thickness of few nanometers, carbon nanotubes, graphene, and molybdenum disulfide thanks to their [...] Read more.

This manuscript presents an overview of the implications of nanomaterials in harvesting ambient electromagnetic waves. We show that the most advanced electromagnetic harvesting devices are based on oxides with a thickness of few nanometers, carbon nanotubes, graphene, and molybdenum disulfide thanks to their unique physical properties. These tiny objects can produce in the years to come a revolution in the harvesting of energy originating from the Sun, heat, or the Earth itself. Full article

(This article belongs to the Special Issue Nanomaterials for Energy Harvesting)

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22 pages, 6318 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Phosphate Capture Enhancement Using Designed Iron Oxide-Based Nanostructures

by Paula Duenas Ramirez, Chaedong Lee, Rebecca Fedderwitz, Antonia R. Clavijo, Débora P. P. Barbosa, Maxime Julliot, Joana Vaz-Ramos, Dominique Begin, Stéphane Le Calvé, Ariane Zaloszyc, Philippe Choquet, Maria A. G. Soler, Damien Mertz, Peter Kofinas, Yuanzhe Piao and Sylvie Begin-Colin

Nanomaterials 2023, 13(3), 587; https://doi.org/10.3390/nano13030587 - 1 Feb 2023

Cited by 4 | Viewed by 2414

Abstract

Phosphates in high concentrations are harmful pollutants for the environment, and new and cheap solutions are currently needed for phosphate removal from polluted liquid media. Iron oxide nanoparticles show a promising capacity for removing phosphates from polluted media and can be easily separated [...] Read more.

Phosphates in high concentrations are harmful pollutants for the environment, and new and cheap solutions are currently needed for phosphate removal from polluted liquid media. Iron oxide nanoparticles show a promising capacity for removing phosphates from polluted media and can be easily separated from polluted media under an external magnetic field. However, they have to display a high surface area allowing high removal pollutant capacity while preserving their magnetic properties. In that context, the reproducible synthesis of magnetic iron oxide raspberry-shaped nanostructures (RSNs) by a modified polyol solvothermal method has been optimized, and the conditions to dope the latter with cobalt, zinc, and aluminum to improve the phosphate adsorption have been determined. These RSNs consist of oriented aggregates of iron oxide nanocrystals, providing a very high saturation magnetization and a superparamagnetic behavior that favor colloidal stability. Finally, the adsorption of phosphates as a function of pH, time, and phosphate concentration has been studied. The undoped and especially aluminum-doped RSNs were demonstrated to be very effective phosphate adsorbents, and they can be extracted from the media by applying a magnet. Full article

(This article belongs to the Special Issue Iron Oxide Nanomaterials)

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11 pages, 3656 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Efficient Solar Light Photocatalyst Made of Ag₃PO₄ Coated TiO₂-SiO₂ Microspheres

by Sudipto Pal, Sanosh Kunjalukkal Padmanabhan, Amruth Kaitheri, Mauro Epifani and Antonio Licciulli

Nanomaterials 2023, 13(3), 588; https://doi.org/10.3390/nano13030588 - 1 Feb 2023

Cited by 2 | Viewed by 1801

Abstract

Solar light active photocatalyst was prepared as silver phosphate (Ag₃PO₄) coating on titania–silica (TiO₂–SiO₂) microspheres. Titania–silica microsphere was obtained by spray drying TiO₂–SiO₂ colloidal solutions, whereas Ag₃PO₄ was applied [...] Read more.

Solar light active photocatalyst was prepared as silver phosphate (Ag₃PO₄) coating on titania–silica (TiO₂–SiO₂) microspheres. Titania–silica microsphere was obtained by spray drying TiO₂–SiO₂ colloidal solutions, whereas Ag₃PO₄ was applied by wet impregnation. XRD on the granules and SEM analysis show that the silver phosphate particles cover the surface of the titania–silica microspheres, and UV-visible diffuse reflectance analysis highlights that Ag₃PO₄/TiO₂–SiO₂ composites can absorb the entire visible light spectrum. BET measurements show higher specific surface area of the composite samples compared to bare Ag₃PO₄. Photocatalytic activity was evaluated by dye degradation tests under solar light irradiation. The prepared catalysts follow a pseudo-first-order rate law for dye degradation tests under solar light irradiation. The composite catalysts with an Ag₃PO₄/TiO₂–SiO₂ ratio of 1:1.6 wt% show better catalytic activity towards both rhodamine B and methylene blue degradation and compared with the results with uncoated TiO₂–SiO₂ microspheres and the benchmark commercial TiO₂ (Evonik-P25) as a reference. The composite photocatalyst showed exceptional efficiency compared to its pristine counterparts and reference material. This is explained as having a higher surface area with optimum light absorption capacity. Full article

(This article belongs to the Special Issue Composite Photocatalysts Based on Nanomaterials)

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13 pages, 4066 KiB

Open AccessEditor’s ChoiceArticle

Preparation and Antibacterial Properties of a Composite Fiber Membrane Material Loaded with Cationic Antibacterial Agent by Electrospinning

by Lin Li, Chengfu Zhang, Lina Tian, Zihang Wu, Dongqing Wang and Tifeng Jiao

Nanomaterials 2023, 13(3), 583; https://doi.org/10.3390/nano13030583 - 1 Feb 2023

Cited by 9 | Viewed by 2207

Abstract

Microbial infections due to bacteria, viruses, and molds are a serious threat to both human life and the health of other organisms. To develop inexpensive, easy-to-prepare, efficient, and portable nano-antibacterial materials, as well as to explore the antibacterial prospects of cationic antibacterial agents, [...] Read more.

Microbial infections due to bacteria, viruses, and molds are a serious threat to both human life and the health of other organisms. To develop inexpensive, easy-to-prepare, efficient, and portable nano-antibacterial materials, as well as to explore the antibacterial prospects of cationic antibacterial agents, in this work, six different membrane materials were prepared by the electrostatic spinning method and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR). The materials were tested for antimicrobial properties using a modified AATCC100-200 test method. Under the most suitable spinning conditions, the doping amount of the cationic antimicrobial agent, CTAB, had the greatest influence on the antimicrobial performance. The antimicrobial performance of PCL/PEO/CS/CTAB_0.4 was the highest among the prepared materials, with 83.7% effectiveness against S. aureus and 99.9% against E. coli. The antimicrobial performance was found to be stable. In our study, we determined the most suitable spinning ratio to prepare an inexpensive and efficient cationic antimicrobial agent. Biodegradable, high-antimicrobial-activity antimicrobial materials can be applied as films, and this new nanofiber material has shown great potential in wound dressings and as a mask material due to its remarkable antimicrobial efficiency. Full article

(This article belongs to the Special Issue Self-Assembled Nanocomposites and Nanostructures for Environmental and Energic Applications)

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11 pages, 12024 KiB

Open AccessEditor’s ChoiceArticle

Rapid Uniformity Analysis of Fully Printed SWCNT-Based Thin Film Transistor Arrays via Roll-to-Roll Gravure Process

by Yunhyok Choi, Younsu Jung, Reem Song, Jinhwa Park, Sajjan Parajuli, Sagar Shrestha, Gyoujin Cho and Byung-Sung Kim

Nanomaterials 2023, 13(3), 590; https://doi.org/10.3390/nano13030590 - 1 Feb 2023

Cited by 3 | Viewed by 2060

Abstract

The roll-to-roll (R2R) gravure process has the potential for manufacturing single-wall carbon nanotubes (SWCNT)-based thin film transistor (TFT) arrays on a flexible plastic substrate. A significant hurdle toward the commercialization of the R2R-printed SWCNT-TFT array is the lack of a suitable, simple, and [...] Read more.

The roll-to-roll (R2R) gravure process has the potential for manufacturing single-wall carbon nanotubes (SWCNT)-based thin film transistor (TFT) arrays on a flexible plastic substrate. A significant hurdle toward the commercialization of the R2R-printed SWCNT-TFT array is the lack of a suitable, simple, and rapid method for measuring the uniformity of printed products. We developed a probing instrument for characterizing R2R gravure printed TFT, named PICR2R-TFT, for rapidly characterizing R2R-printed SWCNT-TFT array that can present a geographical distribution profile to pinpoint the failed devices in an SWCNT-TFT array. Using the newly developed PICR2R-TFT instrument, the current–voltage characteristics of the fabricated SWCNT-TFT devices could be correlated to various R2R-printing process parameters, such as channel length, roll printing length, and printing speed. Thus, by introducing a characterization tool that is reliable and fast, one can quickly optimize the R2R gravure printing conditions to enhance product uniformity, thereby maximizing the yield of printed SWCNT-TFT arrays. Full article

(This article belongs to the Special Issue Nanomaterials for Printed Electronics and Bioelectronics)

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14 pages, 14655 KiB

Open AccessEditor’s ChoiceArticle

Magnetic Properties and Microstructure of FePt(BN, X, C) (X = Ag, Re) Films

by Jai-Lin Tsai, Chun-Yu Sun, Jhih-Hong Lin, Yi-Yuan Huang and He-Ting Tsai

Nanomaterials 2023, 13(3), 539; https://doi.org/10.3390/nano13030539 - 29 Jan 2023

Cited by 2 | Viewed by 1984

Abstract

A sputtered FePt(BN, Re, C) film, here boron nitride (BN), was compared to a reference sample FePt(BN, Ag, C). Intrinsically, these films illustrate a high anisotropy field (H_k) and perpendicular magnetocrystalline anisotropy (K_u),although the reference sample shows a higher [...] Read more.

A sputtered FePt(BN, Re, C) film, here boron nitride (BN), was compared to a reference sample FePt(BN, Ag, C). Intrinsically, these films illustrate a high anisotropy field (H_k) and perpendicular magnetocrystalline anisotropy (K_u),although the reference sample shows a higher value (H_k = 69.5 kOe, K_u = 1.74 × 10⁷ erg/cm³) than the FePt(BN, Re, C) film (H_k = 66.9 kOe, K_u = 1.46 × 10⁷ erg/cm³). However, the small difference in the anisotropy constant (K2/K1) ratio presents a close tendency in the angular dependence of the switching field. Extrinsically, the out-of-plane coercivity for the reference sample is 32 kOe, which is also higher than the FePt(BN, Re, C) film (H_c = 27 kOe), and both films present lower remanence (Mr_(parallel)/Mr_{(perpendicular)} = 0.08~0.12), that is, the index for perpendicular magnetic anisotropy. The higher perpendicular magnetization for both films was due to highly (001) textured FePt films, which was also evidenced by the tight rocking width of 4.1°/3.0° for (001)/(002) X-ray diffraction peaks, respectively, and high-enough ordering degree. The reference sample was measured to have a higher ordering degree (S = 0.84) than FePt(BN, Re, C) (S = 0.63). As a result, the Ag segregant shows stronger ability to promote the ordering of the FePt film; however, the FePt(BN, Re, C) film still has comparable magnetic properties without Ag doping. From the surface and elemental composition analysis, the metallic Re atoms found in the FePt lattice result in a strong spin–orbital coupling between transition metal Fe (3d electron) and heavy metals (Re, Pt) (5d electron) and we conducted high magnetocrystalline anisotropy (K_u). Above is the explanation that the lower-ordered FePt(BN, Re, C) film still has high-enough Ku and out-of-plane Hc. Regarding the microstructure, both the reference sample and FePt(BN, Re, C) show granular structure and columnar grains, and the respective average grain size and distributions are 6.60 nm (12.5%) and 11.2 nm (15.9%). The average widths of the grain boundaries and the aspect ratio of the columnar grain height are 2.05 nm, 1.00 nm, 2.35 nm, and 1.70 nm, respectively. Full article

(This article belongs to the Special Issue Current Research in Magnetic Nanomaterials: From Fundamentals towards Applications)

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27 pages, 5070 KiB

Open AccessEditor’s ChoiceReview

Nanomaterials for Molecular Detection and Analysis of Extracellular Vesicles

by Mitchell Lee Taylor, Anthony Gregory Giacalone, Kristopher Daniel Amrhein, Raymond Edward Wilson, Jr., Yongmei Wang and Xiaohua Huang

Nanomaterials 2023, 13(3), 524; https://doi.org/10.3390/nano13030524 - 28 Jan 2023

Cited by 4 | Viewed by 3253

Abstract

Extracellular vesicles (EVs) have emerged as a novel resource of biomarkers for cancer and certain other diseases. Probing EVs in body fluids has become of major interest in the past decade in the development of a new-generation liquid biopsy for cancer diagnosis and [...] Read more.

Extracellular vesicles (EVs) have emerged as a novel resource of biomarkers for cancer and certain other diseases. Probing EVs in body fluids has become of major interest in the past decade in the development of a new-generation liquid biopsy for cancer diagnosis and monitoring. However, sensitive and specific molecular detection and analysis are challenging, due to the small size of EVs, low amount of antigens on individual EVs, and the complex biofluid matrix. Nanomaterials have been widely used in the technological development of protein and nucleic acid-based EV detection and analysis, owing to the unique structure and functional properties of materials at the nanometer scale. In this review, we summarize various nanomaterial-based analytical technologies for molecular EV detection and analysis. We discuss these technologies based on the major types of nanomaterials, including plasmonic, fluorescent, magnetic, organic, carbon-based, and certain other nanostructures. For each type of nanomaterial, functional properties are briefly described, followed by the applications of the nanomaterials for EV biomarker detection, profiling, and analysis in terms of detection mechanisms. Full article

(This article belongs to the Section Biology and Medicines)

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20 pages, 5268 KiB

Open AccessEditor’s ChoiceArticle

Conferring Antioxidant Activity to an Antibacterial and Bioactive Titanium Surface through the Grafting of a Natural Extract

by Francesca Gamna, Seiji Yamaguchi, Andrea Cochis, Sara Ferraris, Ajay. Kumar, Lia Rimondini and Silvia Spriano

Nanomaterials 2023, 13(3), 479; https://doi.org/10.3390/nano13030479 - 25 Jan 2023

Cited by 6 | Viewed by 2140

Abstract

The main unmet medical need of bone implants is multifunctional activity, including their ability to induce rapid and physiological osseointegration, counteract bacterial biofilm formation, and prevent in situ chronic inflammation at the same time. This research starts from an already developed c.p. titanium [...] Read more.

The main unmet medical need of bone implants is multifunctional activity, including their ability to induce rapid and physiological osseointegration, counteract bacterial biofilm formation, and prevent in situ chronic inflammation at the same time. This research starts from an already developed c.p. titanium surface with proven bioactive (in vitro hydroxyl apatite precipitation) and antibacterial activities, due to a calcium titanate layer with nano- and micro-scale roughness and loaded with iodine ions. Here, antioxidant ability was added to prevent chronic inflammation by grafting polyphenols of a green tea extract onto the surface, without compromising the other functionalities of the surface. The surface was characterized before and after functionalization through XPS analysis, zeta potential titrations, ion release measurements, in vitro bioactivity tests, SEM and fluorescence microscopy, and Folin–Ciocalteu and biological tests. The presence of grafted polyphenols as a homogeneous layer was proven. The grafted polyphenols maintained their antioxidant ability and were anchored to the surface through the linking action of Ca²⁺ ions added to the functionalizing solution. Iodine ion release, cytocompatibility towards human mesenchymal stem cells (hMSC), and antibacterial activity were maintained even after functionalization. The antioxidant ability of the functionalized surface was effective in preserving hMSC viability in a chemically induced pro-inflammatory environment, thus showing a scavenger activity towards toxic active species responsible for inflammation. Full article

(This article belongs to the Special Issue Nanostructured Biomaterials for Tissue Repair and Anti-infection)

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47 pages, 6170 KiB

Open AccessEditor’s ChoiceReview

The State of the Art and Challenges of In Vitro Methods for Human Hazard Assessment of Nanomaterials in the Context of Safe-by-Design

by Nienke Ruijter, Lya G. Soeteman-Hernández, Marie Carrière, Matthew Boyles, Polly McLean, Julia Catalán, Alberto Katsumiti, Joan Cabellos, Camilla Delpivo, Araceli Sánchez Jiménez, Ana Candalija, Isabel Rodríguez-Llopis, Socorro Vázquez-Campos, Flemming R. Cassee and Hedwig Braakhuis

Nanomaterials 2023, 13(3), 472; https://doi.org/10.3390/nano13030472 - 24 Jan 2023

Cited by 11 | Viewed by 4830

Abstract

The Safe-by-Design (SbD) concept aims to facilitate the development of safer materials/products, safer production, and safer use and end-of-life by performing timely SbD interventions to reduce hazard, exposure, or both. Early hazard screening is a crucial first step in this process. In this [...] Read more.

The Safe-by-Design (SbD) concept aims to facilitate the development of safer materials/products, safer production, and safer use and end-of-life by performing timely SbD interventions to reduce hazard, exposure, or both. Early hazard screening is a crucial first step in this process. In this review, for the first time, commonly used in vitro assays are evaluated for their suitability for SbD hazard testing of nanomaterials (NMs). The goal of SbD hazard testing is identifying hazard warnings in the early stages of innovation. For this purpose, assays should be simple, cost-effective, predictive, robust, and compatible. For several toxicological endpoints, there are indications that commonly used in vitro assays are able to predict hazard warnings. In addition to the evaluation of assays, this review provides insights into the effects of the choice of cell type, exposure and dispersion protocol, and the (in)accurate determination of dose delivered to cells on predictivity. Furthermore, compatibility of assays with challenging advanced materials and NMs released from nano-enabled products (NEPs) during the lifecycle is assessed, as these aspects are crucial for SbD hazard testing. To conclude, hazard screening of NMs is complex and joint efforts between innovators, scientists, and regulators are needed to further improve SbD hazard testing. Full article

(This article belongs to the Special Issue Risk Assessment of Nanomaterials Toxicity)

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11 pages, 6390 KiB

Open AccessEditor’s ChoiceArticle

Bulk Photovoltaic Current Mechanisms in All-Inorganic Perovskite Multiferroic Materials

by Jiazheng Chen, Guobin Ma, Boxiang Gong, Chaoyong Deng, Min Zhang, Kaixin Guo, Ruirui Cui, Yunkai Wu, Menglan Lv and Xu Wang

Nanomaterials 2023, 13(3), 429; https://doi.org/10.3390/nano13030429 - 20 Jan 2023

Cited by 7 | Viewed by 2424

Abstract

After the discovery of bulk photovoltaic effect more than half a century ago, ferro-electrical and magneto-optical experiments have provided insights into various related topics, revealing above bandgap open voltages and non-central symmetrical current mechanisms. However, the nature of the photon-generated carriers responses and [...] Read more.

After the discovery of bulk photovoltaic effect more than half a century ago, ferro-electrical and magneto-optical experiments have provided insights into various related topics, revealing above bandgap open voltages and non-central symmetrical current mechanisms. However, the nature of the photon-generated carriers responses and their microscopic mechanisms remain unclear. Here, all-inorganic perovskite Bi

_{0.85}

Gd

_{0.15}

Fe

_{1 - x}

Mn

_{x}

O

_{3}

thin films were prepared by a sol-gel process and the effects of Gd and Mn co-doped bismuth ferrites on their microtopography, grain boundries, multiferroic, and optical properties were studied. We discovered a simple “proof of principle” type new method that by one-step measuring the leakage current, one can demonstrate the value of photo generated current being the sum of ballistic current and shift current, which are combined to form the so-called bulk photovoltaic current, and can be related to the prototype intrinsic properties such as magneto-optical coupling and ferroelectric polarization. This result has significant potential influence on design principles for engineering multiferroic optoelectronic devices and future photovoltaic industry development. Full article

(This article belongs to the Special Issue Advanced Nanomaterials for Perovskite Solar Cells)

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13 pages, 2598 KiB

Open AccessEditor’s ChoiceArticle

Smart Nanofiber Mesh with Locally Sustained Drug Release Enabled Synergistic Combination Therapy for Glioblastoma

by Yinuo Li, Yoshitaka Matsumoto, Lili Chen, Yu Sugawara, Emiho Oe, Nanami Fujisawa, Mitsuhiro Ebara and Hideyuki Sakurai

Nanomaterials 2023, 13(3), 414; https://doi.org/10.3390/nano13030414 - 19 Jan 2023

Cited by 2 | Viewed by 2518

Abstract

This study aims to propose a new treatment model for glioblastoma (GBM). The combination of chemotherapy, molecular targeted therapy and radiotherapy has been achieved in a highly simultaneous manner through the application of a safe, non-toxic, locally sustained drug-releasing composite Nanofiber mesh (NFM). [...] Read more.

This study aims to propose a new treatment model for glioblastoma (GBM). The combination of chemotherapy, molecular targeted therapy and radiotherapy has been achieved in a highly simultaneous manner through the application of a safe, non-toxic, locally sustained drug-releasing composite Nanofiber mesh (NFM). The NFM consisted of biodegradable poly(ε-caprolactone) with temozolomide (TMZ) and 17-allylamino-17-demethoxygeldanamycin (17AAG), which was used in radiation treatment. TMZ and 17AAG combination showed a synergistic cytotoxicity effect in the T98G cell model. TMZ and 17AAG induced a radiation-sensitization effect, respectively. The NFM containing 17AAG or TMZ, known as 17AAG-NFM and TMZ-NFM, enabled cumulative drug release of 34.1% and 39.7% within 35 days. Moreover, 17AAG+TMZ-NFM containing both drugs revealed a synergistic effect in relation to the NFM of a single agent. When combined with radiation, 17AAG+TMZ-NFM induced in an extremely powerful cytotoxic effect. These results confirmed the application of NFM can simultaneously allow multiple treatments to T98G cells. Each modality achieved a significant synergistic effect with the other, leading to a cascading amplification of the therapeutic effect. Due to the superior advantage of sustained drug release over a long period of time, NFM has the promise of clinically addressing the challenge of high recurrence of GBM post-operatively. Full article

(This article belongs to the Special Issue Biohybrid Nanofibers and Nanomaterial-Contained Fibers: Fabrication and Application)

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18 pages, 4045 KiB

Open AccessEditor’s ChoiceArticle

Electrochemical Synthesis, Magnetic and Optical Characterisation of FePd Dense and Mesoporous Nanowires

by Deepti Raj, Gabriele Barrera, Federico Scaglione, Federica Celegato, Matteo Cialone, Marco Coïsson, Paola Tiberto, Jordi Sort, Paola Rizzi and Eva Pellicer

Nanomaterials 2023, 13(3), 403; https://doi.org/10.3390/nano13030403 - 19 Jan 2023

Cited by 1 | Viewed by 2499

Abstract

Dense and mesoporous FePd nanowires (NWs) with 45 to 60 at.% Pd content were successfully fabricated by template- and micelle-assisted pulsed potentiostatic electrodeposition using nanoporous anodic alumina and polycarbonate templates of varying pore sizes. An FePd electrolyte was utilized for obtaining dense NWs [...] Read more.

Dense and mesoporous FePd nanowires (NWs) with 45 to 60 at.% Pd content were successfully fabricated by template- and micelle-assisted pulsed potentiostatic electrodeposition using nanoporous anodic alumina and polycarbonate templates of varying pore sizes. An FePd electrolyte was utilized for obtaining dense NWs while a block copolymer, P-123, was added to this electrolyte as the micelle-forming surfactant to produce mesoporous NWs. The structural and magnetic properties of the NWs were investigated by electron microscopy, X-ray diffraction, and vibrating sample magnetometry. The as-prepared NWs were single phase with a face-centered cubic structure exhibiting 3.1 µm to 7.1 µm of length. Mesoporous NWs revealed a core-shell structure where the porosity was only witnessed in the internal volume of the NW while the outer surface remained non-porous. Magnetic measurements revealed that the samples displayed a soft ferromagnetic behavior that depended on the shape anisotropy and the interwire dipolar interactions. The mesoporous core and dense shell structure of the NWs were seen to be slightly affecting the magnetic properties. Moreover, mesoporous NWs performed excellently as SERS substrates for the detection of 4,4′-bipyridine, showing a low detection limit of 10⁻¹² M. The signal enhancement can be attributed to the mesoporous morphology as well as the close proximity of the embedded NWs being conducive to localized surface plasmon resonance. Full article

(This article belongs to the Special Issue New Challenges in Nanofilm and Nanowire Characterization)

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14 pages, 2218 KiB

Open AccessEditor’s ChoiceArticle

Magnetic Properties of Zig-Zag-Edged Hexagonal Nanohelicenes: A Quantum Chemical Study

by Vitaly Porsev and Robert Evarestov

Nanomaterials 2023, 13(3), 415; https://doi.org/10.3390/nano13030415 - 19 Jan 2023

Cited by 7 | Viewed by 1571

Abstract

The atomic structure and electronic and magnetic properties of two zig-zag-edged hexagonal nanohelicenes of the second type [1.2] and [2.2] were studied by the density functional theory. These objects possess a helical periodicity and belong to the fifth family of line symmetry groups [...] Read more.

The atomic structure and electronic and magnetic properties of two zig-zag-edged hexagonal nanohelicenes of the second type [1.2] and [2.2] were studied by the density functional theory. These objects possess a helical periodicity and belong to the fifth family of line symmetry groups in their global energy minimum. These nanohelicenes were shown by us to be diamagnetic metals that undergo spontaneous symmetry breaking into antiferromagnetic semiconductors as a result of the Mott–Hubbard metal-insulator transition. However, under some torsional stress, a reversible transformation to a diamagnetic metal can take place, which is promising for the use of nanohelicenes in electro-magneto-mechanical nanodevices. Full article

(This article belongs to the Section Theory and Simulation of Nanostructures)

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11 pages, 2416 KiB

Open AccessEditor’s ChoiceArticle

Pixelated Micropolarizer Array Based on Carbon Nanotube Films

by Hui Zhang, Yanji Yi, Yibin Wang, Huwang Hou, Ting Meng, Peng Zhang and Yang Zhao

Nanomaterials 2023, 13(3), 391; https://doi.org/10.3390/nano13030391 - 18 Jan 2023

Viewed by 1341

Abstract

A micropolarizer array (MPA) that can be integrated into a scientific camera is proposed as a real-time polarimeter that is capable of extracting the polarization parameters. The MPA is based on highly aligned carbon nanotube (CNT) films inspired by their typical anisotropy and [...] Read more.

A micropolarizer array (MPA) that can be integrated into a scientific camera is proposed as a real-time polarimeter that is capable of extracting the polarization parameters. The MPA is based on highly aligned carbon nanotube (CNT) films inspired by their typical anisotropy and selectivity for light propagation over a wide spectral range. The MPA contains a dual-tier CNT pixel plane with 0° and 45° orientations. The thickness of the dual-tier structure of the CNT-based MPA is limited to less than 2 μm with a pixel size of 7.45 μm × 7.45 μm. The degree of polarization of the CNT-MPA reached 93% at a 632 nm wavelength. The specific designs in structure and semiconductor fabrication procedures are described. Compared with customary MPAs, CNT-based MPA holds great potential in decreasing the cross-talk risk associated with lower film thickness and can be extended to a wide spectral range. Full article

(This article belongs to the Special Issue 2D Materials for Advanced Sensors: Fabrication and Applications)

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16 pages, 4936 KiB

Open AccessEditor’s ChoiceArticle

Graphene-Based Coating to Mitigate Biofilm Development in Marine Environments

by Francisca Sousa-Cardoso, Rita Teixeira-Santos, Ana Francisca Campos, Marta Lima, Luciana C. Gomes, Olívia S. G. P. Soares and Filipe J. Mergulhão

Nanomaterials 2023, 13(3), 381; https://doi.org/10.3390/nano13030381 - 18 Jan 2023

Cited by 8 | Viewed by 3133

Abstract

Due to its several economic and ecological consequences, biofouling is a widely recognized concern in the marine sector. The search for non-biocide-release antifouling coatings has been on the rise, with carbon-nanocoated surfaces showing promising activity. This work aimed to study the impact of [...] Read more.

Due to its several economic and ecological consequences, biofouling is a widely recognized concern in the marine sector. The search for non-biocide-release antifouling coatings has been on the rise, with carbon-nanocoated surfaces showing promising activity. This work aimed to study the impact of pristine graphene nanoplatelets (GNP) on biofilm development through the representative marine bacteria Cobetia marina and to investigate the antibacterial mechanisms of action of this material. For this purpose, a flow cytometric analysis was performed and a GNP/polydimethylsiloxane (PDMS) surface containing 5 wt% GNP (G5/PDMS) was produced, characterized, and assessed regarding its biofilm mitigation potential over 42 days in controlled hydrodynamic conditions that mimic marine environments. Flow cytometry revealed membrane damage, greater metabolic activity, and endogenous reactive oxygen species (ROS) production by C. marina when exposed to GNP 5% (w/v) for 24 h. In addition, C. marina biofilms formed on G5/PDMS showed consistently lower cell count and thickness (up to 43% reductions) than PDMS. Biofilm architecture analysis indicated that mature biofilms developed on the graphene-based surface had fewer empty spaces (34% reduction) and reduced biovolume (25% reduction) compared to PDMS. Overall, the GNP-based surface inhibited C. marina biofilm development, showing promising potential as a marine antifouling coating. Full article

(This article belongs to the Special Issue Nano-Enhanced Strategies for Biofouling and Biocorrosion Prevention)

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39 pages, 30620 KiB

Open AccessEditor’s ChoiceReview

Dynamics and Processes on Laser-Irradiated Surfaces

by Juergen Reif

Nanomaterials 2023, 13(3), 379; https://doi.org/10.3390/nano13030379 - 17 Jan 2023

Cited by 2 | Viewed by 2758

Abstract

The modification of solid surfaces via the impacts of intense laser pulses and the dynamics of the relevant processes are reviewed. We start with rather weak interactions on dielectric materials, based on non-linear absorption across the bandgap and resulting in low-level local effects [...] Read more.

The modification of solid surfaces via the impacts of intense laser pulses and the dynamics of the relevant processes are reviewed. We start with rather weak interactions on dielectric materials, based on non-linear absorption across the bandgap and resulting in low-level local effects like electron and individual ion emission. The role of such locally induced defects in the cumulative effect of incubation, i.e., the increase in efficiency with the increasing number of laser pulses, is addressed. At higher excitation density levels, due to easier laser–material coupling and higher laser fluence, the energy dissipation is considerable, leading to lattice destabilization, surface relaxation, ablation, and surface modification (e.g., laser-induced periodic surface structures). Finally, a short list of possible applications, namely in the field of wettability, is presented. Full article

(This article belongs to the Special Issue Dynamics and Processes at Laser-Irradiated Surfaces—A Themed Issue in Honor of the 70th Birthday of Professor Jürgen Reif)

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20 pages, 3843 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Uranium Removal from Aqueous Solutions by Aerogel-Based Adsorbents—A Critical Review

by Efthalia Georgiou, Grigorios Raptopoulos, Ioannis Anastopoulos, Dimitrios A. Giannakoudakis, Michael Arkas, Patrina Paraskevopoulou and Ioannis Pashalidis

Nanomaterials 2023, 13(2), 363; https://doi.org/10.3390/nano13020363 - 16 Jan 2023

Cited by 16 | Viewed by 3661

Abstract

Aerogels are a class of lightweight, nanoporous, and nanostructured materials with diverse chemical compositions and a huge potential for applications in a broad spectrum of fields. This has led the IUPAC to include them in the top ten emerging technologies in chemistry for [...] Read more.

Aerogels are a class of lightweight, nanoporous, and nanostructured materials with diverse chemical compositions and a huge potential for applications in a broad spectrum of fields. This has led the IUPAC to include them in the top ten emerging technologies in chemistry for 2022. This review provides an overview of aerogel-based adsorbents that have been used for the removal and recovery of uranium from aqueous environments, as well as an insight into the physicochemical parameters affecting the adsorption efficiency and mechanism. Uranium removal is of particular interest regarding uranium analysis and recovery, to cover the present and future uranium needs for nuclear power energy production. Among the methods used, such as ion exchange, precipitation, and solvent extraction, adsorption-based technologies are very attractive due to their easy and low-cost implementation, as well as the wide spectrum of adsorbents available. Aerogel-based adsorbents present an extraordinary sorption capacity for hexavalent uranium that can be as high as 8.8 mol kg^–1 (2088 g kg^–1). The adsorption data generally follow the Langmuir isotherm model, and the kinetic data are in most cases better described by the pseudo-second-order kinetic model. An evaluation of the thermodynamic data reveals that the adsorption is generally an endothermic, entropy-driven process (ΔH⁰, ΔS⁰ > 0). Spectroscopic studies (e.g., FTIR and XPS) indicate that the adsorption is based on the formation of inner-sphere complexes between surface active moieties and the uranyl cation. Regeneration and uranium recovery by acidification and complexation using carbonate or chelating ligands (e.g., EDTA) have been found to be successful. The application of aerogel-based adsorbents to uranium removal from industrial processes and uranium-contaminated waste waters was also successful, assuming that these materials could be very attractive as adsorbents in water treatment and uranium recovery technologies. However, the selectivity of the studied materials towards hexavalent uranium is limited, suggesting further developments of aerogel materials that could be modified by surface derivatization with chelating agents (e.g., salophen and iminodiacetate) presenting high selectivity for uranyl moieties. Full article

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

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13 pages, 2679 KiB

Open AccessEditor’s ChoiceArticle

Numerical and Experimental Study of Colored Magnetic Particle Mapping via Magnetoelectric Sensors

by Ron-Marco Friedrich, Mohammad Sadeghi and Franz Faupel

Nanomaterials 2023, 13(2), 347; https://doi.org/10.3390/nano13020347 - 14 Jan 2023

Cited by 3 | Viewed by 2075

Abstract

Colored imaging of magnetic nanoparticles (MNP) is a promising noninvasive method for medical applications such as therapy and diagnosis. This study investigates the capability of the magnetoelectric sensor and projected gradient descent (PGD) algorithm for colored particle detection. In the first step, the [...] Read more.

Colored imaging of magnetic nanoparticles (MNP) is a promising noninvasive method for medical applications such as therapy and diagnosis. This study investigates the capability of the magnetoelectric sensor and projected gradient descent (PGD) algorithm for colored particle detection. In the first step, the required circumstances for image reconstruction are studied via a simulation approach for different signal-to-noise ratios (SNR). The spatial accuracy of the reconstructed image is evaluated based on the correlation coefficient (CC) factor. The inverse problem is solved using the PGD method, which is adapted according to a nonnegativity constraint in the complex domain. The MNP characterizations are assessed through a magnetic particle spectrometer (MPS) for different types. In the experimental investigation, the real and imaginary parts of the MNP’s response are used to detect the spatial distribution and particle type, respectively. The experimental results indicate that the average phase difference for CT100 and ARA100 particles is 14 degrees, which is consistent with the MPS results and could satisfy the system requirements for colored imaging. The experimental evaluation showed that the magnetoelectric sensor and the proposed approach could be potential candidates for color bio-imaging applications. Full article

(This article belongs to the Special Issue Perspectives in Magnetoelectric and Magnetic Nanomaterials)

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10 pages, 2258 KiB

Open AccessEditor’s ChoiceArticle

Synthesis of Nanocrystalline PuO₂ by Hydrothermal and Thermal Decomposition of Pu(IV) Oxalate: A Comparative Study

by Viktoria Baumann, Karin Popa, Olaf Walter, Murielle Rivenet, Gérald Senentz, Bertrand Morel and Rudy J.M. Konings

Nanomaterials 2023, 13(2), 340; https://doi.org/10.3390/nano13020340 - 13 Jan 2023

Cited by 4 | Viewed by 8486

Abstract

In recent years, the hydrothermal conversion of actinide (IV) oxalates into nanometric actinide dioxides (AnO₂) has begun to be investigated as an alternative to the widely implemented thermal decomposition method. We present here a comparison between the hydrothermal and [...] Read more.

In recent years, the hydrothermal conversion of actinide (IV) oxalates into nanometric actinide dioxides (AnO₂) has begun to be investigated as an alternative to the widely implemented thermal decomposition method. We present here a comparison between the hydrothermal and the conventional thermal decomposition of Pu(IV) oxalate in terms of particle size, morphology and residual carbon content. A parametric study was carried out in order to define the temperature and time applied in the hydrothermal conversion of tetravalent Pu-oxalate into PuO₂ and to optimize the reaction conditions. Full article

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8 pages, 2345 KiB

Open AccessEditor’s ChoiceCommunication

High-Performance n-Type Bi₂Te₃ Thermoelectric Fibers with Oriented Crystal Nanosheets

by Min Sun, Pengyu Zhang, Guowu Tang, Dongdan Chen, Qi Qian and Zhongmin Yang

Nanomaterials 2023, 13(2), 326; https://doi.org/10.3390/nano13020326 - 12 Jan 2023

Cited by 7 | Viewed by 1965

Abstract

High-performance thermoelectric fibers with n-type bismuth telluride (Bi₂Te₃) core were prepared by thermal drawing. The nanosheet microstructures of the Bi₂Te₃ core were tailored by the whole annealing and Bridgman annealing processes, respectively. The influence of the [...] Read more.

High-performance thermoelectric fibers with n-type bismuth telluride (Bi₂Te₃) core were prepared by thermal drawing. The nanosheet microstructures of the Bi₂Te₃ core were tailored by the whole annealing and Bridgman annealing processes, respectively. The influence of the annealing processes on the microstructure and thermoelectric performance was investigated. As a result of the enhanced crystalline orientation of Bi₂Te₃ core caused by the above two kinds of annealing processes, both the electrical conductivity and thermal conductivity could be improved. Hence, the thermoelectric performance was enhanced, that is, the optimized dimensionless figure of merit (ZT) after the Bridgman annealing processes increased from 0.48 to about 1 at room temperature. Full article

(This article belongs to the Special Issue Advanced Nanoscale Materials for Thermoelectric Applications)

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14 pages, 5939 KiB

Open AccessEditor’s ChoiceArticle

The Local and Electronic Structure Study of Lu_xGd_1−xVO₄ (0 ≤ x ≤ 1) Solid Solution Nanocrystals

by Yang Chen, Ziqing Li, Nianjing Ji, Chenxi Wei, Xiulan Duan and Huaidong Jiang

Nanomaterials 2023, 13(2), 323; https://doi.org/10.3390/nano13020323 - 12 Jan 2023

Viewed by 1829

Abstract

Rare-earth-doped mixed crystals have demonstrated tunable optical properties, and it is of great importance to study the structural characteristics of the mixed-crystal hosts. Herein, Lu_xGd_1-xVO₄ (0 ≤ x ≤ 1) solid solution nanocrystals were synthesized by a [...] Read more.

Rare-earth-doped mixed crystals have demonstrated tunable optical properties, and it is of great importance to study the structural characteristics of the mixed-crystal hosts. Herein, Lu_xGd_1-xVO₄ (0 ≤ x ≤ 1) solid solution nanocrystals were synthesized by a modified sol–gel method, with a pure crystalline phase and element composition. The X-ray diffraction (XRD) and Rietveld refinement results showed that Lu_xGd_1−xVO₄ nanocrystals are continuous solid solutions with a tetragonal zircon phase (space group I4₁/amd) and the lattice parameters strictly follow Vegard’s law. The detailed local structures were studied by extended X-ray absorption fine structure (EXAFS) spectra, which revealed that the average bond length of Gd-O fluctuates and decreases, while the average bond length of Lu-O gradually decreases with the increase in Lu content. Furthermore, the binding energy differences of core levels indicate that the covalent V-O bond is relatively stable, while the ionicity of the Lu-O bond decreases with the increasing x value, and the ionicity of the Gd-O bond fluctuates with small amplitude. The valence band structures were further confirmed by the first-principles calculations, indicating that the valence band is contributed to by the O 2p nonbonding state, localized Gd 4f and Lu 4f states, and the hybridized states between the bonding O 2p and V 3d. The binding energies of the Lu core and the valence levels tend to decrease gradually with the increase in Lu content. This work provides insight into the structural features of mixed-crystal hosts, which have been developed in recent years to improve laser performance by providing different positions for active ions to obtain inhomogeneous broadening spectra. Full article

(This article belongs to the Special Issue Optoelectronic Functional Nanomaterials and Devices)

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13 pages, 2584 KiB

Open AccessEditor’s ChoiceArticle

Rational Optimization of Cathode Composites for Sulfide-Based All-Solid-State Batteries

by Artur Tron, Raad Hamid, Ningxin Zhang and Alexander Beutl

Nanomaterials 2023, 13(2), 327; https://doi.org/10.3390/nano13020327 - 12 Jan 2023

Cited by 8 | Viewed by 4477

Abstract

All-solid-state lithium-ion batteries with argyrodite solid electrolytes have been developed to attain high conductivities of 10⁻³ S cm⁻¹ in studies aiming at fast ionic conductivity of electrolytes. However, no matter how high the ionic conductivity of the electrolyte, the design of [...] Read more.

All-solid-state lithium-ion batteries with argyrodite solid electrolytes have been developed to attain high conductivities of 10⁻³ S cm⁻¹ in studies aiming at fast ionic conductivity of electrolytes. However, no matter how high the ionic conductivity of the electrolyte, the design of the cathode composite is often the bottleneck for high performance. Thus, optimization of the composite cathode formulation is of utmost importance. Unfortunately, many reports limit their studies to only a few parameters of the whole electrode formulation. In addition, different measurement setups and testing conditions employed for all-solid-state batteries make a comparison of results from mutually independent studies quite difficult. Therefore, a detailed investigation on different key parameters for preparation of cathodes employed in all-solid-state batteries is presented here. Employing a rational approach for optimization of composite cathodes using solid sulfide electrolytes elucidated the influence of different parameters on the cycling performance. First, powder electrodes made without binders are investigated to optimize several parameters, including the active materials’ particle morphology, the nature and amount of the conductive additive, the particle size of the solid electrolyte, as well as the active material-to-solid electrolyte ratio. Finally, cast electrodes are examined to determine the influence of a binder on cycling performance. Full article

(This article belongs to the Special Issue Sulfur Based Nanomaterials for Secondary Batteries)

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13 pages, 15211 KiB

Open AccessEditor’s ChoiceArticle

In Vitro Analysis of Superparamagnetic Iron Oxide Nanoparticles Coated with APTES as Possible Radiosensitizers for HNSCC Cells

by Clara Emer, Laura S. Hildebrand, Bernhard Friedrich, Rainer Tietze, Rainer Fietkau and Luitpold V. Distel

Nanomaterials 2023, 13(2), 330; https://doi.org/10.3390/nano13020330 - 12 Jan 2023

Cited by 1 | Viewed by 2392

Abstract

Superparamagnetic iron oxide nanoparticles (SPION) are being investigated for many purposes, e.g., for the amplification of ionizing radiation and for the targeted application of therapeutics. Therefore, we investigated SPIONs coated with (3-Aminopropyle)-Triethoxysilane (SPION-APTES) for their influence on different head and neck squamous cell [...] Read more.

Superparamagnetic iron oxide nanoparticles (SPION) are being investigated for many purposes, e.g., for the amplification of ionizing radiation and for the targeted application of therapeutics. Therefore, we investigated SPIONs coated with (3-Aminopropyle)-Triethoxysilane (SPION-APTES) for their influence on different head and neck squamous cell carcinoma (HNSCC) cell lines, as well as for their suitability as a radiosensitizer. We used 24-well microscopy and immunofluorescence microscopy for cell observation, growth curves to determine cytostatic effects, and colony formation assays to determine cytotoxicity. We found that the APTES-SPIONs were very well taken up by the HNSCC cells. They generally have a low cytotoxic effect, showing no significant difference in clonogenic survival between the control group and cells treated with 20 µg Fe/mL (p > 0.25) for all cell lines. They have a cytostatic effect on some cell lines cells (e.g., Cal33) that is visible across different radiation doses (1, 2, 8 Gy, p = 0.05). In Cal33, e.g., SPION-APTES raised the doubling time at 2 Gy from 24.53 h to 41.64 h. Importantly, these findings vary notably between the cell lines. However, they do not significantly alter the radiation effect: only one out of eight cell lines treated with SPION-APTES showed a significantly reduced clonogenic survival after ionizing radiation with 2 Gy, and only two showed significantly reduced doubling times. Thus, although the APTES-SPIONs do not qualify as a radiosensitizer, we were still able to vividly demonstrate and analyze the effect that the APTES-SPIONs have on various cell lines as a contribution to further functionalization. Full article

(This article belongs to the Section Biology and Medicines)

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14 pages, 1996 KiB

Open AccessEditor’s ChoiceReview

Upscaling of Carbon-Based Perovskite Solar Module

by Maurizio Stefanelli, Luigi Vesce and Aldo Di Carlo

Nanomaterials 2023, 13(2), 313; https://doi.org/10.3390/nano13020313 - 12 Jan 2023

Cited by 18 | Viewed by 5331

Abstract

Perovskite solar cells (PSCs) and modules are driving the energy revolution in the coming photovoltaic field. In the last 10 years, PSCs reached efficiency close to the silicon photovoltaic technology by adopting low-cost solution processes. Despite this, the noble metal (such as gold [...] Read more.

Perovskite solar cells (PSCs) and modules are driving the energy revolution in the coming photovoltaic field. In the last 10 years, PSCs reached efficiency close to the silicon photovoltaic technology by adopting low-cost solution processes. Despite this, the noble metal (such as gold and silver) used in PSCs as a counter electrode made these devices costly in terms of energy, CO₂ footprint, and materials. Carbon-based perovskite solar cells (C-PSCs) and modules use graphite/carbon-black-based material as the counter electrode. The formulation of low-cost carbon-based inks and pastes makes them suitable for large area coating techniques and hence a solid technology for imminent industrialization. Here, we want to present the upscaling routes of carbon-counter-electrode-based module devices in terms of materials formulation, architectures, and manufacturing processes in order to give a clear vision of the scaling route and encourage the research in this green and sustainable direction. Full article

(This article belongs to the Special Issue Bio-Inspired Functional Nanomaterials)

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12 pages, 2089 KiB

Open AccessEditor’s ChoiceArticle

Dietary Transfer of Zinc Oxide Nanoparticles Induces Locomotive Defects Associated with GABAergic Motor Neuron Damage in Caenorhabditis elegans

by Chun Ming How and Chi-Wei Huang

Nanomaterials 2023, 13(2), 289; https://doi.org/10.3390/nano13020289 - 10 Jan 2023

Cited by 7 | Viewed by 1916

Abstract

The widespread use of zinc oxide nanoparticles (ZnO-NPs) and their release into the environment have raised concerns about the potential toxicity caused by dietary transfer. However, the toxic effects and the mechanisms of dietary transfer of ZnO-NPs have rarely been investigated. We employed [...] Read more.

The widespread use of zinc oxide nanoparticles (ZnO-NPs) and their release into the environment have raised concerns about the potential toxicity caused by dietary transfer. However, the toxic effects and the mechanisms of dietary transfer of ZnO-NPs have rarely been investigated. We employed the bacteria-feeding nematode Caenorhabditis elegans as the model organism to investigate the neurotoxicity induced by exposure to ZnO-NPs via trophic transfer. Our results showed that ZnO-NPs accumulated in the intestine of C. elegans and also in Escherichia coli OP50 that they ingested. Additionally, impairment of locomotive behaviors, including decreased body bending and head thrashing frequencies, were observed in C. elegans that were fed E. coli pre-treated with ZnO-NPs, which might have occurred because of damage to the D-type GABAergic motor neurons. However, these toxic effects were not apparent in C. elegans that were fed E. coli pre-treated with zinc chloride (ZnCl₂). Therefore, ZnO-NPs particulates, rather than released Zn ions, damage the D-type GABAergic motor neurons and adversely affect the locomotive behaviors of C. elegans via dietary transfer. Full article

(This article belongs to the Special Issue Nanoparticles in the Environment and Nanotoxicology)

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13 pages, 4226 KiB

Open AccessEditor’s ChoiceArticle

In Situ Grown Mesoporous Structure of Fe-Dopant@NiCoO_X@NF Nanoneedles as an Efficient Supercapacitor Electrode Material

by Yedluri Anil Kumar, Ganesh Koyyada, Dasha Kumar Kulurumotlakatla, Jae Hong Kim, Md Moniruzzaman, Salem Alzahmi and Ihab M. Obaidat

Nanomaterials 2023, 13(2), 292; https://doi.org/10.3390/nano13020292 - 10 Jan 2023

Cited by 5 | Viewed by 2792

Abstract

In this study, we designed mixed metal oxides with doping compound nano-constructions as efficient electrode materials for supercapacitors (SCs). We successfully prepared the Fe-dopant with NiCoO_x grown on nickel foam (Fe-dopant@NiCoO_x@NF) through a simple hydrothermal route with annealing procedures. This [...] Read more.

In this study, we designed mixed metal oxides with doping compound nano-constructions as efficient electrode materials for supercapacitors (SCs). We successfully prepared the Fe-dopant with NiCoO_x grown on nickel foam (Fe-dopant@NiCoO_x@NF) through a simple hydrothermal route with annealing procedures. This method provides an easy route for the preparation of high activity SCs for energy storage. Obtained results revealed that the Fe dopant has successfully assisted NiCoO_x lattices. The electrochemical properties were investigated in a three-electrode configuration. As a composite electrode for SC characteristics, the Fe-dopant@NiCoO_x@NF exhibits notable electrochemical performances with very high specific capacitances of 1965 F g⁻¹ at the current density of 0.5 A g⁻¹, and even higher at 1296 F g⁻¹ and 30 A g⁻¹, respectively, which indicate eminent and greater potential for SCs. Moreover, the Fe-dopant@NiCoO_x@NF nanoneedle composite obtains outstanding cycling performances of 95.9% retention over 4500 long cycles. The improved SC activities of Fe-dopant@NiCoO_x@NF nanoneedles might be ascribed to the synergistic reactions of the ternary mixed metals, Fe-dopant, and the ordered nanosheets grown on NF. Thus, the Fe-dopant@NiCoO_x@NF nanoneedle composite with unique properties could lead to promising SC performance. Full article

(This article belongs to the Special Issue Advanced Functional Nanomaterials for Energy Storage Applications, Volume II)

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12 pages, 9453 KiB

Open AccessEditor’s ChoiceArticle

Supercurrent in Bi₄Te₃ Topological Material-Based Three-Terminal Junctions

by Jonas Kölzer, Abdur Rehman Jalil, Daniel Rosenbach, Lisa Arndt, Gregor Mussler, Peter Schüffelgen, Detlev Grützmacher, Hans Lüth and Thomas Schäpers

Nanomaterials 2023, 13(2), 293; https://doi.org/10.3390/nano13020293 - 10 Jan 2023

Cited by 7 | Viewed by 2544

Abstract

In this paper, in an in situ prepared three-terminal Josephson junction based on the topological insulator Bi

_{4}

Te

_{3}

and the superconductor Nb the transport properties are studied. The differential resistance maps as a function of two bias currents reveal extended areas [...] Read more.

In this paper, in an in situ prepared three-terminal Josephson junction based on the topological insulator Bi

_{4}

Te

_{3}

and the superconductor Nb the transport properties are studied. The differential resistance maps as a function of two bias currents reveal extended areas of Josephson supercurrent, including coupling effects between adjacent superconducting electrodes. The observed dynamics for the coupling of the junctions is interpreted using a numerical simulation of a similar geometry based on a resistively and capacitively shunted Josephson junction model. The temperature dependency indicates that the device behaves similar to prior experiments with single Josephson junctions comprising topological insulators’ weak links. Irradiating radio frequencies to the junction, we find a spectrum of integer Shapiro steps and an additional fractional step, which is interpreted with a skewed current–phase relationship. In a perpendicular magnetic field, we observe Fraunhofer-like interference patterns in the switching currents. Full article

(This article belongs to the Special Issue Topological Materials in Low Dimensions)

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19 pages, 6251 KiB

Open AccessEditor’s ChoiceArticle

Photocatalytic Degradation of Crystal Violet Dye under Visible Light by Fe-Doped TiO₂ Prepared by Reverse-Micelle Sol–Gel Method

by Antonietta Mancuso, Nicola Blangetti, Olga Sacco, Francesca Stefania Freyria, Barbara Bonelli, Serena Esposito, Diana Sannino and Vincenzo Vaiano

Nanomaterials 2023, 13(2), 270; https://doi.org/10.3390/nano13020270 - 8 Jan 2023

Cited by 36 | Viewed by 4342

Abstract

A reverse-micelle sol–gel method was chosen for the preparation of Fe-doped TiO₂ samples that were employed in the photodegradation of the crystal violet dye under visible light irradiation in a batch reactor. The dopant amount was varied to assess the optimal photocatalyst [...] Read more.

A reverse-micelle sol–gel method was chosen for the preparation of Fe-doped TiO₂ samples that were employed in the photodegradation of the crystal violet dye under visible light irradiation in a batch reactor. The dopant amount was varied to assess the optimal photocatalyst composition towards the target dye degradation. The photocatalysts were characterized through a multi-technique approach, envisaging XRPD and QPA as obtained by Rietveld refinement, FE-SEM analysis, DR UV−vis spectroscopy, N₂ adsorption/desorption isotherms measurement at −196 °C, ζ-potential measurement, and XPS analysis. The physical-chemical characterization showed that the adopted synthesis method allows obtaining NPs with uniform shape and size and promotes the introduction of Fe into the titania matrix, finally affecting the relative amounts of the three occurring polymorphs of TiO₂ (anatase, rutile and brookite). By increasing the Fe content, the band gap energy decreases from 3.13 eV (with undoped TiO₂) to 2.65 eV (with both 2.5 and 3.5 wt.% nominal Fe contents). At higher Fe content, surface Fe oxo-hydroxide species occur, as shown by DR UV-vis and XP spectroscopies. All the Fe-doped TiO₂ photocatalysts were active in the degradation and mineralization of the target dye, showing a TOC removal higher than the undoped sample. The photoactivity under visible light was ascribed both to the band-gap reduction (as confirmed by phenol photodegradation) and to dye sensitization of the photocatalyst surface (as confirmed by photocatalytic tests carried out using different visible-emission spectra LEDs). The main reactive species involved in the dye degradation were determined to be positive holes. Full article

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18 pages, 2191 KiB

Open AccessEditor’s ChoiceReview

Recent Strategies for High-Performing Indoor Perovskite Photovoltaics

by Kelvian T. Mularso, Ji-Young Jeong, Gill Sang Han and Hyun Suk Jung

Nanomaterials 2023, 13(2), 259; https://doi.org/10.3390/nano13020259 - 7 Jan 2023

Cited by 9 | Viewed by 4154

Abstract

The development of digital technology has made our lives more advanced as a society familiar with the Internet of Things (IoT). Solar cells are among the most promising candidates for power supply in IoT sensors. Perovskite photovoltaics (PPVs), which have already attained 25% [...] Read more.

The development of digital technology has made our lives more advanced as a society familiar with the Internet of Things (IoT). Solar cells are among the most promising candidates for power supply in IoT sensors. Perovskite photovoltaics (PPVs), which have already attained 25% and 40% power conversion efficiencies for outdoor and indoor light, respectively, are the best candidates for self-powered IoT system integration. In this review, we discuss recent research progress on PPVs under indoor light conditions, with a focus on device engineering to achieve high-performance indoor PPVs (Id-PPVs), including bandgap optimization and defect management. Finally, we discuss the challenges of Id-PPVs development and its interpretation as a potential research direction in the field. Full article

(This article belongs to the Special Issue New Horizon in Perovskite Nanocrystals)

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13 pages, 2379 KiB

Open AccessEditor’s ChoiceArticle

Wearable and Washable MnO₂−Zn Battery Packaged by Vacuum Sealing

by Jun Ho Noh, Myoungeun Oh, Sunjin Kang, Hyeong Seok Lee, Yeong Jun Hong, Chaeyeon Park, Raeyun Lee and Changsoon Choi

Nanomaterials 2023, 13(2), 265; https://doi.org/10.3390/nano13020265 - 7 Jan 2023

Cited by 3 | Viewed by 2584

Abstract

Batteries are used in all types of electronic devices from conventional to advanced devices. Currently, batteries are evolving in the direction of extremely personalized yarn− or textile−structured textronic systems. However, the absence of a protective layer on such batteries is a critical limitation [...] Read more.

Batteries are used in all types of electronic devices from conventional to advanced devices. Currently, batteries are evolving in the direction of extremely personalized yarn− or textile−structured textronic systems. However, the absence of a protective layer on such batteries is a critical limitation to their practical use. In this study, we developed a wearable and washable MnO₂−Zn textile battery that maintains its electrochemical capacity under various external environmental conditions through a vacuum−sealed packaging. The packaged textile battery was fabricated by vacuuming a polymer envelope containing the battery, followed by heat sealing with a vacuum packaging machine. The interior and exterior regions of the textile battery are completely separated by the packaging sheath to preclude leakage and intrusion of substances. The resulting packaged textile battery exhibits stable capacity retention performance under varying temperature and humidity; mechanical deformations due to bending, twisting, rubbing, and pressing; and several mechanical, chemical, and their combined washing cycles. On the basis of these demonstrations, we expect that our vacuum−packaged textile battery will offer new possibilities for practical and convenient use of textronics. Full article

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14 pages, 3545 KiB

Open AccessEditor’s ChoiceArticle

K_xCo_1.5−0.5xFe(CN)₆/rGO with Dual−Active Sodium Ion Storage Site as Superior Anode for Sodium Ion Battery

by Gang Zhou, Mincong Fan, Lei Wang, Xianglin Li, Danqing Liu and Feng Gao

Nanomaterials 2023, 13(2), 264; https://doi.org/10.3390/nano13020264 - 7 Jan 2023

Cited by 1 | Viewed by 1966

Abstract

The unique and open large frame structures of prussian blue analogues (PBA) enables it for accommodating a large number of cations (Na⁺, K⁺, Ca²⁺, etc.), thus, PBA are considered as promising electrode materials for the rechargeable battery. [...] Read more.

The unique and open large frame structures of prussian blue analogues (PBA) enables it for accommodating a large number of cations (Na⁺, K⁺, Ca²⁺, etc.), thus, PBA are considered as promising electrode materials for the rechargeable battery. However, due to the chemical composition, there are still many alkaline metal ions in the gap within the framework, which puts multivalent metals in PBA in a low valence state and affects the sodium storage performance. To improve the valence of metal ions in PBA materials, precursors prepared by co−precipitation method and hydrothermal method are used to synthesis K_xCo_1.5−0.5xFe(CN)₆ through further chemical oxidation. Through the introducing of reduced graphene oxide (rGO) with excellent conductivity by a simple physical mixing method, the cycle stability and rate performance of the PBA material can be further improved. The K_0.5Co_1.2Fe(CN)₆·2H₂O/rGO anode prepared with 2 h hydrothermal time and further chemical oxidation, named as KCoHCP−H2−EK/rGO, exhibits a super electrochemical performance, delivering initial charge/discharge capacities of 846.7/1445.0 mAh·g⁻¹, and a capacity retention of 58.2% after 100 cycles at a current density of 100 mA·g⁻¹. The KCoHCP−H2−EK/rGO outstanding electrochemical behaviors are attributed to the unique dual−active site structure properties and the improved surface conductance of materials by rGO components. Full article

(This article belongs to the Special Issue Functional Micro-/Nanostructures: Advanced Fabrication and Application)

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10 pages, 1719 KiB

Open AccessEditor’s ChoiceArticle

Capacitive NO₂ Detection Using CVD Graphene-Based Device

by Wonbin Ju and Sungbae Lee

Nanomaterials 2023, 13(2), 243; https://doi.org/10.3390/nano13020243 - 5 Jan 2023

Cited by 3 | Viewed by 1856

Abstract

A graphene-based capacitive NO₂ sensing device was developed by utilizing the quantum capacitance effect. We have used a graphene field-effect transistor (G-FET) device whose geometrical capacitance is enhanced by incorporating an aluminum back-gate electrode with a naturally oxidized aluminum surface as an [...] Read more.

A graphene-based capacitive NO₂ sensing device was developed by utilizing the quantum capacitance effect. We have used a graphene field-effect transistor (G-FET) device whose geometrical capacitance is enhanced by incorporating an aluminum back-gate electrode with a naturally oxidized aluminum surface as an insulating layer. When the graphene, the top-side of the device, is exposed to NO₂, the quantum capacitance of graphene and, thus, the measured capacitance of the device, changed in accordance with NO₂ concentrations ranging from 1–100 parts per million (ppm). The operational principle of the proposed system is also explained with the changes in gate voltage-dependent capacitance of the G-FET exposed to various concentrations of NO₂. Further analyses regarding carrier density changes and potential variances under various concentrations of NO₂ are also presented to strengthen the argument. The results demonstrate the feasibility of capacitive NO₂ sensing using graphene and the operational principle of capacitive NO₂ sensing. Full article

(This article belongs to the Special Issue Mechanical Properties and Applications of Graphene and Layered Nanocomposites)

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14 pages, 6255 KiB

Open AccessEditor’s ChoiceArticle

Effect of Polyphenols on the Ice-Nucleation Activity of Ultrafine Bubbles

by Tsutomu Uchida and Yukiharu Fukushi

Nanomaterials 2023, 13(1), 205; https://doi.org/10.3390/nano13010205 - 2 Jan 2023

Cited by 2 | Viewed by 2564

Abstract

Ultrafine bubbles (UFBs) in water provide a large amount of gas and a large gas–liquid interfacial area, and can release energy through their collapse. Such features may promote ice nucleation. Here, we examined the nucleation of ice in solutions containing polyphenols and UFBs. [...] Read more.

Ultrafine bubbles (UFBs) in water provide a large amount of gas and a large gas–liquid interfacial area, and can release energy through their collapse. Such features may promote ice nucleation. Here, we examined the nucleation of ice in solutions containing polyphenols and UFBs. To reduce the likelihood of nucleation occurring on the container walls over that in previous studies, we used a much larger sample volume of 1 mL. In our experiments, UFBs (when present) had a number concentration of 10⁸ mL⁻¹. We quantified changes to the nucleation activity by examining the shift in the cumulative freezing (nucleation) probability distribution. Compared to pure water, this freezing curve shifts approximately 0.6 °C higher with the UFBs. Then, to the water, we added three polyphenols (tannic acid TA, tea catechin TC, and oligonol OLG), chosen because they had been reported to reduce the ice-nucleation activity of heterogeneous ice nuclei (e.g., AgI). We found experimentally that, without UFBs, all polyphenols instead shift the pure-water freezing curve to a higher temperature. Then, when UFBs are added, the additional temperature shift in the freezing curve is slightly higher for OLG, essentially unchanged for TA, and slightly lower for TC. To help to explain these differences, we examined the UFB size distributions using dynamic light scattering and freeze-fractured replicas with transmission electron microscopy, finding that OLG and TC alter the UFBs, but that TA does not. Full article

(This article belongs to the Special Issue Nanobubbles and Their Applications)

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10 pages, 2935 KiB

Open AccessEditor’s ChoiceArticle

Improved Electrical Properties of EHD Jet-Patterned MoS₂ Thin-Film Transistors with Printed Ag Electrodes on a High-k Dielectric

by Thi Thu Thuy Can and Woon-Seop Choi

Nanomaterials 2023, 13(1), 194; https://doi.org/10.3390/nano13010194 - 1 Jan 2023

Cited by 5 | Viewed by 2306

Abstract

Electrohydrodynamic (EHD) jet printing is known as a versatile method to print a wide viscosity range of materials that are impossible to print by conventional inkjet printing. Hence, with the understanding of the benefits of EHD jet printing, solution-based MoS₂ and a [...] Read more.

Electrohydrodynamic (EHD) jet printing is known as a versatile method to print a wide viscosity range of materials that are impossible to print by conventional inkjet printing. Hence, with the understanding of the benefits of EHD jet printing, solution-based MoS₂ and a high-viscosity Ag paste were EHD jet-printed for electronic applications in this work. In particular, printed MoS₂ TFTs with a patterned Ag source and drain were successfully fabricated with low-k silica (SiO₂) and high-k alumina (Al₂O₃) gate dielectrics, respectively. Eventually, the devices based on Al₂O₃ exhibited much better electrical properties compared to the ones based on SiO₂. Interestingly, an improvement of around one order of magnitude in hysteresis was achieved for devices after changing the gate insulator from SiO₂ to Al₂O₃. In effect, the results of this work for the printed MoS₂ and the printed Ag source and drains for TFTs demonstrate a new approach for jet printing in the fabrication of electronic devices. Full article

(This article belongs to the Special Issue 2D Semiconducting Materials for Device Applications)

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16 pages, 5060 KiB

Open AccessEditor’s ChoiceArticle

Photodetection Properties of MoS₂, WS₂ and Mo_xW_1-xS₂ Heterostructure: A Comparative Study

by Maryam Al Qaydi, Ahmed Kotbi, Nitul S. Rajput, Abdellatif Bouchalkha, Mimoun El Marssi, Guillaume Matras, Chaouki Kasmi and Mustapha Jouiad

Nanomaterials 2023, 13(1), 24; https://doi.org/10.3390/nano13010024 - 21 Dec 2022

Cited by 8 | Viewed by 3516

Abstract

Layered transition metals dichalcogenides such as MoS₂ and WS₂ have shown a tunable bandgap, making them highly desirable for optoelectronic applications. Here, we report on one-step chemical vapor deposited MoS₂, WS₂ and Mo_xW_1-xS₂ [...] Read more.

Layered transition metals dichalcogenides such as MoS₂ and WS₂ have shown a tunable bandgap, making them highly desirable for optoelectronic applications. Here, we report on one-step chemical vapor deposited MoS₂, WS₂ and Mo_xW_1-xS₂ heterostructures incorporated into photoconductive devices to be examined and compared in view of their use as potential photodetectors. Vertically aligned MoS₂ nanosheets and horizontally stacked WS₂ layers, and their heterostructure form Mo_xW_1-xS₂, exhibit direct and indirect bandgap, respectively. To analyze these structures, various characterization methods were used to elucidate their properties including Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectrometry and high-resolution transmission electron microscopy. While all the investigated samples show a photoresponse in a broad wavelength range between 400 nm and 700 nm, the vertical MoS₂ nanosheets sample exhibits the highest performances at a low bias voltage of 5 V. Our findings demonstrate a responsivity and a specific detectivity of 47.4 mA W⁻¹ and 1.4 × 10¹¹ Jones, respectively, achieved by Mo_xW_1-xS₂. This study offers insights into the use of a facile elaboration technique for tuning the performance of Mo_xW_1-xS₂ heterostructure-based photodetectors. Full article

(This article belongs to the Special Issue Advances in Nanostructured Semiconductors and Heterojunctions)

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15 pages, 4473 KiB

Open AccessEditor’s ChoiceArticle

Shear Bond Strength and Color Stability of Novel Antibacterial Nanofilled Dental Adhesive Resins

by Qing Hong, Alexandra C. Pierre-Bez, Matheus Kury, Mark E. Curtis, Rochelle D. Hiers, Fernando L. Esteban Florez and John C. Mitchell

Nanomaterials 2023, 13(1), 1; https://doi.org/10.3390/nano13010001 - 20 Dec 2022

Cited by 9 | Viewed by 2307

Abstract

Experimental adhesives containing co-doped metaloxide nanoparticles were demonstrated to display strong and long-term antibacterial properties against Streptococcus mutans biofilms. The present study represents an effort to characterize the shear-bond strength (SBS) and color stability (CS) of these novel biomaterials. Experimental adhesives were obtained [...] Read more.

Experimental adhesives containing co-doped metaloxide nanoparticles were demonstrated to display strong and long-term antibacterial properties against Streptococcus mutans biofilms. The present study represents an effort to characterize the shear-bond strength (SBS) and color stability (CS) of these novel biomaterials. Experimental adhesives were obtained by dispersing nitrogen and fluorine co-doped titanium dioxide nanoparticles (NF_TiO₂, 10%, 20% or 30%, v/v%) into OptiBond Solo Plus (OPTB). Dentin surfaces were wet-polished (600-Grit). Specimens (n = 5/group) of Tetric EvoCeram were fabricated and bonded using either OPTB or experimental (OPTB + NF_TiO₂) adhesives. Specimens were stored in water (37 °C) for twenty-four hours (T1), three months (T2), and six months (T3). At T1, T2, or T3, specimens were removed from water storage and were tested for SBS. Disc-shaped specimens (n = 10/group; d = 6.0 mm, t = 0.5 mm) of adhesives investigated were fabricated and subjected to thermocycling (10,000 cycles, 5–55 °C, 15 s dwell time). Specimens’ colors were determined with a VITA Easyshade^® V spectrophotometer (after every 1000 cycles). SBS data was analyzed using two-way ANOVA and post-hoc Tukey tests, while CS data was analyzed using one-way ANOVA and post-hoc Tukey tests (α = 0.05). Mean values of SBS ranged from 16.39 ± 4.20 MPa (OPTB + 30%NF_TiO₂) to 19.11 ± 1.11 MPa (OPTB), from 12.99 ± 2.53 MPa (OPTB + 30% NF_TiO₂) to 14.87 ± 2.02 (OPTB) and from 11.37 ± 1.89 (OPTB + 20% NF_TiO₂) to 14.19 ± 2.24 (OPTB) after twenty-four hours, three months, and six months of water storage, respectively. Experimental materials had SBS values that were comparable (p > 0.05) to those from OPTB independently of nanoparticle concentration or time-point considered. Experimental materials with higher NF_TiO₂ concentrations had less intense color variations and were more color stable than OPTB even after 10,000 thermocycles. In combination, the results reported have demonstrated that experimental adhesives can establish strong and durable bonds to human dentin while displaying colors that are more stable, thereby suggesting that the antibacterial nanotechnology investigated can withstand the harsh conditions within the oral cavity without compromising the esthetic component of dental restorations. Full article

(This article belongs to the Special Issue Synthesis and Application of Nanoparticles in Novel Composites)

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16 pages, 6500 KiB

Open AccessEditor’s ChoiceArticle

Insights into the Stability of Graphene Oxide Aqueous Dispersions

by Codrut Costinas, Catalin Alexandru Salagean, Liviu Cosmin Cotet, Monica Baia, Milica Todea, Klara Magyari and Lucian Baia

Nanomaterials 2022, 12(24), 4489; https://doi.org/10.3390/nano12244489 - 19 Dec 2022

Cited by 7 | Viewed by 2070

Abstract

Understanding graphene oxide’s stability (or lack thereof) in liquid solvents is critical for fine-tuning the material’s characteristics and its potential involvement in future applications. In this work, through the use of structural and surface investigations, the alteration of the structural and edge-surface properties [...] Read more.

Understanding graphene oxide’s stability (or lack thereof) in liquid solvents is critical for fine-tuning the material’s characteristics and its potential involvement in future applications. In this work, through the use of structural and surface investigations, the alteration of the structural and edge-surface properties of 2D graphene oxide nanosheets was monitored over a period of eight weeks by involving DLS, zeta potential, XRD, XPS, Raman and FT-IR spectroscopy techniques. The samples were synthesized as an aqueous suspension by an original modified Marcano-Tour method centred on the sono-chemical exfoliation of graphite. Based on the acquired experimental results and the available literature, a phenomenological explanation of the two underlying mechanisms responsible for the meta-stability of graphene oxide aqueous dispersions is proposed. It is based on the cleavage of the carbon bonds in the first 3–4 weeks, while the bonding of oxygen functional groups on the carbon lattice occurs, and the transformation of epoxide and hydroxyl groups into adsorbed water molecules in a process driven by the availability of hydrogen in graphene oxide nanosheets. Full article

(This article belongs to the Special Issue Synthesis, Modification and Application of Graphene)

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11 pages, 2429 KiB

Open AccessEditor’s ChoiceArticle

Biocompatibility, Bioactivity, and Antibacterial Behaviour of Cerium-Containing Bioglass^®

by Sílvia R. Gavinho, Ana Sofia Pádua, Isabel Sá-Nogueira, Jorge C. Silva, João P. Borges, Luis C. Costa and Manuel Pedro F. Graça

Nanomaterials 2022, 12(24), 4479; https://doi.org/10.3390/nano12244479 - 18 Dec 2022

Cited by 23 | Viewed by 3020

Abstract

The main reason for the increased use of dental implants in clinical practice is associated with aesthetic parameters. Implants are also presented as the only technique that conserves and stimulates natural bone. However, there are several problems associated with infections, such as peri-implantitis. [...] Read more.

The main reason for the increased use of dental implants in clinical practice is associated with aesthetic parameters. Implants are also presented as the only technique that conserves and stimulates natural bone. However, there are several problems associated with infections, such as peri-implantitis. This disease reveals a progressive inflammatory action that affects the hard and soft tissues surrounding the implant, leading to implant loss. To prevent the onset of this disease, coating the implant with bioactive glasses has been suggested. In addition to its intrinsic function of promoting bone regeneration, it is also possible to insert therapeutic ions, such as cerium. Cerium has several advantages when the aim is to improve osseointegration and prevent infectious problems with dental implant placement. It promotes increased growth and the differentiation of osteoblasts, improves the mechanical properties of bone, and prevents bacterial adhesion and proliferation that may occur on the implant surface. This antibacterial effect is due to its ability to disrupt the cell wall and membrane of bacteria, thus interfering with vital metabolic functions such as respiration. In addition, its antioxidant effect reverses oxidative stress after implantation in bone. In this work, Bioglass 45S5 with CeO₂ with different percentages (0.25, 0.5, 1, and 2 mol%) was developed by the melt-quenching method. The materials were analyzed in terms of morphological, structural, and biological (cytotoxicity, bioactivity, and antibacterial activity) properties. The addition of cerium did not promote structural changes to the bioactive glass, which shows no cytotoxicity for the Saos-2 cell line up to 25 mg/mL of extract concentration for all cerium contents. For the maximum cerium concentration (2 mol%) the bioactive glass shows an evident inhibitory effect for Escherichia coli and Streptococcus mutans bacteria. Furthermore, all samples showed the beginning of the deposition of a CaP-rich layer on the surface of the material after 24 h. Full article

(This article belongs to the Special Issue Nanobiotechnologies in Environment and Medicine)

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19 pages, 5643 KiB

Open AccessEditor’s ChoiceArticle

3D Nanoprinting of All-Metal Nanoprobes for Electric AFM Modes

by Lukas Matthias Seewald, Jürgen Sattelkow, Michele Brugger-Hatzl, Gerald Kothleitner, Hajo Frerichs, Christian Schwalb, Stefan Hummel and Harald Plank

Nanomaterials 2022, 12(24), 4477; https://doi.org/10.3390/nano12244477 - 17 Dec 2022

Cited by 7 | Viewed by 2266

Abstract

3D nanoprinting via focused electron beam induced deposition (FEBID) is applied for fabrication of all-metal nanoprobes for atomic force microscopy (AFM)-based electrical operation modes. The 3D tip concept is based on a hollow-cone (HC) design, with all-metal material properties and apex radii in [...] Read more.

3D nanoprinting via focused electron beam induced deposition (FEBID) is applied for fabrication of all-metal nanoprobes for atomic force microscopy (AFM)-based electrical operation modes. The 3D tip concept is based on a hollow-cone (HC) design, with all-metal material properties and apex radii in the sub-10 nm regime to allow for high-resolution imaging during morphological imaging, conductive AFM (CAFM) and electrostatic force microscopy (EFM). The study starts with design aspects to motivate the proposed HC architecture, followed by detailed fabrication characterization to identify and optimize FEBID process parameters. To arrive at desired material properties, e-beam assisted purification in low-pressure water atmospheres was applied at room temperature, which enabled the removal of carbon impurities from as-deposited structures. The microstructure of final HCs was analyzed via scanning transmission electron microscopy—high-angle annular dark field (STEM-HAADF), whereas electrical and mechanical properties were investigated in situ using micromanipulators. Finally, AFM/EFM/CAFM measurements were performed in comparison to non-functional, high-resolution tips and commercially available electric probes. In essence, we demonstrate that the proposed all-metal HCs provide the resolution capabilities of the former, with the electric conductivity of the latter onboard, combining both assets in one design. Full article

(This article belongs to the Special Issue Nanomaterials Fabricated by Electron-Beam-Induced Deposition and Related Processes)

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35 pages, 2188 KiB

Open AccessEditor’s ChoiceReview

Mechanisms of Antifungal Properties of Metal Nanoparticles

by Yael N. Slavin and Horacio Bach

Nanomaterials 2022, 12(24), 4470; https://doi.org/10.3390/nano12244470 - 16 Dec 2022

Cited by 51 | Viewed by 5811

Abstract

The appearance of resistant species of fungi to the existent antimycotics is challenging for the scientific community. One emergent technology is the application of nanotechnology to develop novel antifungal agents. Metal nanoparticles (NPs) have shown promising results as an alternative to classical antimycotics. [...] Read more.

The appearance of resistant species of fungi to the existent antimycotics is challenging for the scientific community. One emergent technology is the application of nanotechnology to develop novel antifungal agents. Metal nanoparticles (NPs) have shown promising results as an alternative to classical antimycotics. This review summarizes and discusses the antifungal mechanisms of metal NPs, including combinations with other antimycotics, covering the period from 2005 to 2022. These mechanisms include but are not limited to the generation of toxic oxygen species and their cellular target, the effect of the cell wall damage and the hyphae and spores, and the mechanisms of defense implied by the fungal cell. Lastly, a description of the impact of NPs on the transcriptomic and proteomic profiles is discussed. Full article

(This article belongs to the Special Issue Development of Nanomaterials for Biomedical Applications)

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20 pages, 2945 KiB

Open AccessEditor’s ChoiceArticle

Towards Improved Humidity Sensing Nanomaterials via Combined Electron and NH₃ Treatment of Carbon-Rich FEBID Deposits

by Hannah Boeckers, Petra Swiderek and Markus Rohdenburg

Nanomaterials 2022, 12(24), 4455; https://doi.org/10.3390/nano12244455 - 15 Dec 2022

Cited by 1 | Viewed by 1881

Abstract

Focused Electron Beam Induced Deposition (FEBID) is a unique tool to produce nanoscale materials. The resulting deposits can be used, for instance, as humidity or strain sensors. The humidity sensing concept relies on the fact that FEBID using organometallic precursors often yields deposits [...] Read more.

Focused Electron Beam Induced Deposition (FEBID) is a unique tool to produce nanoscale materials. The resulting deposits can be used, for instance, as humidity or strain sensors. The humidity sensing concept relies on the fact that FEBID using organometallic precursors often yields deposits which consist of metal nanoparticles embedded in a carbonaceous matrix. The electrical conductivity of such materials is altered in the presence of polar molecules such as water. Herein, we provide evidence that the interaction with water can be enhanced by incorporating nitrogen in the deposit through post-deposition electron irradiation in presence of ammonia (NH₃). This opens the perspective to improve and tune the properties of humidity sensors fabricated by FEBID. As a proof-of-concept experiment, we have prepared carbonaceous deposits by electron irradiation of adsorbed layers of three different precursors, namely, the aliphatic hydrocarbon n-pentane, a simple alkene (2-methyl-2-butene), and the potential Ru FEBID precursor bis(ethylcyclopentadienyl)ruthenium(II). In a subsequent processing step, we incorporated C-N bonds in the deposit by electron irradiation of adsorbed NH₃. To test the resulting material with respect to its potential humidity sensing capabilities, we condensed sub-monolayer quantities of water (H₂O) on the deposit and evaluated their thermal desorption behavior. The results confirm that the desorption temperature of H₂O decisively depends on the degree of N incorporation into the carbonaceous residue which, in turn, depends on the chemical nature of the precursor used for deposition of the carbonaceous layer. We thus anticipate that the sensitivity of a FEBID-based humidity sensor can be tuned by a precisely timed post-deposition electron and NH₃ processing step. Full article

(This article belongs to the Special Issue Nanomaterials Fabricated by Electron-Beam-Induced Deposition and Related Processes)

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14 pages, 4899 KiB

Open AccessEditor’s ChoiceArticle

Electrical Contact Resistance of Large-Area Graphene on Pre-Patterned Cu and Au Electrodes

by Tomáš Blecha, Zuzana Vlčková Živcová, Farjana J. Sonia, Martin Mergl, Oleksandr Volochanskyi, Michal Bodnár, Pavel Rous, Kenichiro Mizohata, Martin Kalbáč and Otakar Frank

Nanomaterials 2022, 12(24), 4444; https://doi.org/10.3390/nano12244444 - 14 Dec 2022

Cited by 4 | Viewed by 3118

Abstract

Contact resistance between electrically connected parts of electronic elements can negatively affect their resulting properties and parameters. The contact resistance is influenced by the physicochemical properties of the connected elements and, in most cases, the lowest possible value is required. The issue of [...] Read more.

Contact resistance between electrically connected parts of electronic elements can negatively affect their resulting properties and parameters. The contact resistance is influenced by the physicochemical properties of the connected elements and, in most cases, the lowest possible value is required. The issue of contact resistance is also addressed in connection with the increasingly frequently used carbon allotropes. This work aimed to determine the factors that influence contact resistance between graphene prepared by chemical vapour deposition and pre-patterned Cu and Au electrodes onto which graphene is subsequently transferred. It was found that electrode surface treatment methods affect the resistance between Cu and graphene, where contact resistance varied greatly, with an average of 1.25 ± 1.54 kΩ, whereas for the Au electrodes, the deposition techniques did not influence the resulting contact resistance, which decreased by almost two orders of magnitude compared with the Cu electrodes, to 0.03 ± 0.01 kΩ. Full article

(This article belongs to the Special Issue Nanofabrication and Nanomanipulation in Graphene)

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20 pages, 2617 KiB

Open AccessEditor’s ChoiceArticle

Interaction of Colloidal Gold Nanoparticles with Urine and Saliva Biofluids: An Exploratory Study

by Maria António, Tânia Lima, Rui Vitorino and Ana L. Daniel-da-Silva

Nanomaterials 2022, 12(24), 4434; https://doi.org/10.3390/nano12244434 - 13 Dec 2022

Cited by 2 | Viewed by 2173

Abstract

The use of gold nanoparticles for drug delivery, photothermal or photodynamic therapy, and biosensing enhances the demand for knowledge about the protein corona formed on the surface of nanoparticles. In this study, gold nanospheres (AuNSs), gold nanorods (AuNRs), and gold nanoflowers (AuNFs) were [...] Read more.

The use of gold nanoparticles for drug delivery, photothermal or photodynamic therapy, and biosensing enhances the demand for knowledge about the protein corona formed on the surface of nanoparticles. In this study, gold nanospheres (AuNSs), gold nanorods (AuNRs), and gold nanoflowers (AuNFs) were incubated with saliva or urine. After the interaction, the surface of gold nanoparticles was investigated using UV-VIS spectroscopy, zeta potential, and dynamic light scattering. The shifting of the localized surface plasmon resonance (LSPR) band, the increase in hydrodynamic diameter, and the changes in the surface charge of nanoparticles indicated the presence of biomolecules on the surface of AuNSs, AuNRs, and AuNFs. The incubation of AuNFs with saliva led to nanoparticle aggregation and minimal protein adsorption. AuNSs and AuNRs incubated in saliva were analyzed through liquid chromatography with tandem mass spectrometry (LC-MS/MS) to identify the 96 proteins adsorbed on the surface of the gold nanoparticles. Among the 20 most abundant proteins identified, 14 proteins were common in both AuNSs and AuNRs. We hypothesize that the adsorption of these proteins was due to their high sulfur content, allowing for their interaction with gold nanoparticles via the Au-S bond. The presence of distinct proteins on the surface of AuNSs or AuNRs was also investigated and possibly related to the competition between proteins present on the external layers of corona and gold nanoparticle morphology. Full article

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