Search Results (2,440)

Nanotextured thin film metallic glasses (TFMGs) have emerged as promising antimicrobial coatings for biomedical applications; however, systematic comparisons across compositionally distinct Ti- and Zr-based systems, as well as their early-stage bactericidal mechanisms, remain limited. Here, we show, for the first time, a comparative, compositionally resolved correlation linking alloy chemistry, nanotexture, and bactericidal mechanisms across polymorphic TFMGs. Three co-sputtered biocompatible coatings (Ti₄₇Fe₄₁Cu₁₂, Zr₇₁Fe₃Al₂₆, and Zr₅₈W₃₁Cu₁₁) were deposited on medical-grade titanium and stainless steel (SS316L) via magnetron co-sputtering, producing uniform amorphous films (190–298 nm) with nanoscale roughness of 1.6 ± 0.05 to 8.1 ± 0.05 nm. Surface wettability spanned hydrophilic (71.1 ± 5.6°) to hydrophobic (106.5 ± 3.5°), modulating bacterial interactions. Antimicrobial performance against Pseudomonas aeruginosa was evaluated using live/dead fluorescence imaging, quantitative image analysis, and electron microscopy after 2–4 h incubation. All coatings reduced bacterial adhesion and viability relative to bare substrates, with Zr₅₈W₃₁Cu₁₁ achieving >60% reduction in surface-associated bacterial coverage. Time-resolved analysis revealed a rapid transition to predominantly non-viable populations on coated surfaces, in contrast to sustained viability on controls. Mechanistically, bactericidal activity arises from the synergistic coupling of nanotopography-induced membrane stress, wettability-governed adhesion energetics, and in situ formation of CuO, Fe₂O₃, WO₃, and ZrO₂ oxides that promote electrostatic interactions and proposed reactive oxygen species generation, driving oxidative membrane damage. These results establish a scalable design framework for TFMGs, while highlighting the need for long-term biofilm and electrochemical validation. Full article

C-reactive protein (CRP) is one of the most essential biomarkers for the early detection of inflammation and infection. In this study, we developed a sensitive and selective electrochemical immunosensor for CRP detection, leveraging the unique properties of gold nanoparticles (AuNPs). A nanostructured layer of AuNPs was deposited onto a screen-printed carbon electrode (SPCE), followed by the formation of a self-assembled monolayer (SAM) of L-cysteine and EDC/sulfo-NHS chemistry. The antibody was covalently immobilized onto the modified electrode through optimized dual-crosslinking chemistry. Detection conditions were systematically optimized, with pH 8.0 in Tris buffer providing the best electrochemical response. Electrochemical characterization was performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) in a 5 mM K₃[Fe(CN)₆]/K₄[Fe(CN)₆] redox probe solution containing 0.1 M KCl. CRP detection was achieved by monitoring the increase in charge transfer resistance (Rct) upon specific binding of the target CRP antigen to the immobilized antibody. Spiked recovery experiments showed spiked recovery rates ranging from 98.01% to 107.14%, with a standard deviation below 4%. Regeneration studies demonstrated high efficiency, confirming the suitability of the sensor interface for repeated and reliable measurements. Under optimized conditions, the immunosensor exhibited excellent analytical performance, including a low limit of detection (LOD) of 0.16 µg/mL, a wide linear detection range of 5–100 µg/mL, high selectivity against 13 potential interferents (including inflammatory cytokines), and good reproducibility with a relative standard deviation (RSD) of 3.69%. The sensor also showed strong stability, retaining more than 95% of its signal after 15 days, and high regeneration efficiency of 97% over seven cycles. These results highlight the strong potential of the proposed immunosensor for point-of-care (POC) applications due to its simple fabrication, cost-effectiveness, user accessibility, and robust analytical performance. Full article

Lamellar structure Ni-P catalysts were prepared on copper by the electrochemical deposition method for the hydrolysis of NaBH₄ solution. Voltage, time and temperature are key variables in the electroplating process, affecting the corrosion performance of the catalyst. The results show that as the deposition voltage (4–7 V) increases, the corrosion resistance of Ni-P at first is enhanced and then decreases, peaking at 5 V due to a more complete structure. Electroplating time and temperature affect the deposition of the nickel-phosphorus catalyst and then the corrosion resistance of the catalyst. Prolonged time and elevated temperature cause holes and cracks, degrading corrosion resistance. Therefore, a mild electroplating environment is preferred. The optimal electroplating temperature and time are 30 °C and 3 min, respectively. The polarization curve test shows that the Ni-P catalyst is greatly influenced by seawater temperature and chloride ion concentration in the actual service process, that the chloride ion is the dominant factor, and that the corrosion rate increases exponentially. Moreover, Ni-P/Cu catalysts mainly undergo localized corrosion and dissolution. Combined with Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS) analyses, the corrosion mechanism in seawater was systematically discussed. Full article

Bowl-shaped gold nanoparticles (BAuNPs) are of significant interest due to their tunable localized surface plasmon resonance (LSPR) properties. This report presents a new synthesis method that uses hemispherical hydrogen nanobubbles on planar, non-conducting surfaces as templates for gold shell deposition. Initial synthesis under stagnant conditions yielded non-uniform sub-micron particles, attributed to localized hydrogen concentration gradients. The cyclonic flow was introduced aiming to reduce these gradients, although simultaneously inducing significant particle aggregation, obscuring the open structure. To overcome these challenges, an electrochemical microfluidic system was implemented to create a laminar flow environment. This configuration optimizes ion distribution and introduces shear forces that promote particle detachment, successfully limiting particle dimensions to below 200 nm, and preventing the accumulation. Systematic optimization identified optimal parameters: an ideal channel length of 7.5 mm, an applied potential of −0.6 V, and a flow rate of 0.028 µL s⁻¹. These parameters that strike a balance between nanobubble growth and gold deposition kinetics can produce highly uniform BAuNPs with a well-defined open structure and thin solid gold shells, with an outer diameter of 105.3 ± 12.1 nm and a core diameter of 80.1 ± 11.9 nm. These structural parameters successfully shift the plasmonic resonance to 760 nm, which responds perfectly with the first biological window for potential in vivo biomedical applications. Full article

The selective oxidative transformation of 5-hydroxymethylfurfural (HMF) is a key route toward producing a wide variety of chemicals in the biorefinery industry. Herein, we report a NiAl layered double hydroxide (NiAl-LDH) catalyst as a highly effective electrocatalytic oxidation catalyst for the transformation of HMF into 2,5-diformylfuran (DFF), a valuable furan-based chemical, with about 75.53% DFF selectivity under neutral conditions. It demonstrated good stability without deactivation after 9 cycles of repeated electrolysis. The NiAl-LDH electrocatalyst was deposited on a nickel foam support via a hydrothermal method, and its structural properties and surface morphology were extensively investigated. Systematic studies of reaction temperature, current intensity, and electrolyte concentration revealed that the neutral electrolyte plays a critical role in achieving high DFF selectivity by suppressing aldehyde over-oxidation. Mechanistic investigations with electrochemically active surface area (ECSA), electrochemical impedance spectroscopy (EIS), Tafel slope and density functional theory (DFT) calculations revealed that the reversible transformation between Ni(OH)₂ and active NiOOH species in the NiAl-LDH electrocatalyst was the main reason for the oxidation of HMF, while the incorporation of Al provided structural support to the electrode, enabling the catalyst to exhibit excellent stability during electrolysis. Overall, this work demonstrates an active, earth-abundant metal electrocatalyst for the valorization of biomass-derived 5-HMF to DFF. Full article

The increasing environmental pollution with emergent pollutants has led to the necessity to develop various structures for sensory applications used in water monitoring processes. In this context, this study presents a composite structure based on titanium foil/titanium dioxide/reduced graphene oxide functionalized with gold ions (Ti/TiO₂-Au/rGO) obtained by a simple and efficient spin-coating method, successfully applied in electrochemical doxorubicin detection processes. The synthesis protocol first involves etching the titanium foil to form a Ti/TiO₂ substrate, followed by the synthesis of the TiO₂-Au/rGO solution, which was deposited by a spin-coating technique on the surface of the Ti/TiO₂ support, to form electrodes based on a Ti/TiO₂-Au/rGO composite structure. The structure and morphology of the as-synthesized composites were investigated in detail using X-ray analysis, Raman spectroscopy, and scanning electron microscopy coupled with an EDX. Furthermore, to determine the electroactive surface area and apparent diffusion coefficient of the composite structures, the electrochemical behavior was evaluated by CV in a 1 M KNO₃ and in the presence of 4 mM K₃Fe(CN)₆. By using electrochemical impedance spectroscopy (EIS) in 0.1 M NaOH supporting electrolyte and within a frequency range of 0.1–10,000 Hz and a voltage of 10 mV, the charge transfer resistance was also investigated. The potential application in electroanalysis of the electrodes was tested by CV for the detection of the DOX pollutant in 0.1 M NaOH and 1–5 mg L⁻¹ DOX. The obtained results provide new insights into the development of electrochemical sensors for applications in water treatment processes. Full article

The growing penetration of renewable energy sources has intensified the demand for safe, sustainable, and cost-effective energy-storage technologies. Aqueous lithium-ion batteries are promising candidates because of their intrinsic safety and high ionic conductivity, though their deployment is limited by narrow electrochemical stability window of water. Lithium titanate oxide (LTO) has emerged as an ideal anode material for aqueous systems because of its exceptional structural stability, negligible volume change during lithiation/delithiation, and relatively high operating potential that suppresses hydrogen evolution. This review examines the peer-reviewed literature (2010–2026) on LTO-based aqueous lithium-ion batteries, focusing on the interdependence between material synthesis, electrode fabrication, electrolyte engineering, and electrochemical performance. Scalable fabrication techniques, such as spray deposition and tape casting, are discussed alongside their pact on electrode quality. Attention is given to water-in-salt, gel-polymer, and localized high-concentration electrolytes that expand the stability window and improve interfacial behavior. Overall, the review highlights how electrolyte design, electrode architecture, and processing methods can be jointly tailored to support stable and scalable LTO-based aqueous lithium-ion batteries systems. Full article

Additive manufacturing (AM) has revolutionized industrial production. However, the repair of AM components remains a critical challenge due to their unique microstructural features. While repair approaches for conventionally manufactured alloys are well established, their direct transferability to AM parts remains largely unexplored due to the unique thermal history and anisotropic microstructure of additive components. This study investigates a novel repair and improvement strategy for Powder Bed Fusion–Laser Beam/Metal (PBF-LB/M)-fabricated AlSi10Mg components, combining Electrospark Deposition (ESD) for dimensional restoration with subsequent Ultrasonic Peening Treatment (UPT) for surface enhancement. Microstructure, porosity, surface roughness, hardness profiles, residual stresses, and corrosion behaviour were systematically characterized using SEM, optical microscopy, profilometry, Vickers microhardness testing, XRD, and electrochemical polarization tests. The results show that the ESD process is capable of producing coatings with excellent interfacial adhesion to the substrate, with an initial porosity of 3.6 ± 0.5%. The subsequent UPT induces a significant densification effect on the deposited material, reducing porosity by approximately 50% and increasing surface hardness by up to 48% in the upper region of the coating. Furthermore, XRD analysis reveals that UPT completely reverses the residual stress state from tensile (typical of the ESD process) to compressive in all measured directions, thereby improving the overall structural integrity. Ultimately, the combined ESD + UPT alters the electrochemical response of AlSi10Mg deposits, resulting in a nobler corrosion potential, albeit with a slightly higher corrosion current density. Full article

Precise control of copper electrodeposition is essential for electrochemical additive manufacturing based on layer-by-layer growth. In this work, the influence of selected organic additives, nicotinic acid, benzotriazole, thiourea and urea in sulfate-based electroplating baths was investigated with respect to their applicability in electrodeposition-driven 3D printing. Linear sweep voltammetry (LSV) was used to analyze the electrochemical behavior of Cu(II) reduction, while copper layers were deposited under potentiostatic conditions in a flow-assisted system (potential controlled conditions). The obtained deposits were characterized by SEM/EDS and quantitative measurements of layer thickness and dendrite height. The results show that the additives strongly affect both deposition kinetics and the morphology of electrodeposited layers. Benzotriazole acts as a strong inhibitor, producing fine-grained structures but reducing deposition efficiency and not fully suppressing vertical growth instabilities. Thiourea leads to highly unstable deposition with excessive dendritic growth and increased impurity incorporation. Nicotinic acid enables relatively thick deposits with moderate dendrite formation within an optimal concentration range. In contrast, urea provides the most stable growth, yielding uniform layers with minimal dendritic development and high copper purity. The dendrite height-to-layer thickness ratio proved to be an effective descriptor of electrodeposition growth stability. These findings highlight the critical role of additive selection in optimizing electroplating baths for electrochemical 3D printing applications. Full article

Hydrogen represents a promising clean and renewable energy source. Therefore, improving the efficiency of electrocatalysts is essential for effective hydrogen production. In this work, Ni electrocatalysts were synthesized via the electrodeposition method from ethaline deep eutectic solvent (DES) at 45 °C, 55 °C, and 65 °C under perpendicular (B_⊥) and parallel (B_‖) magnetic field directions relative to the electrode surface. Scanning electron microscopy (SEM) was employed to investigate the morphological study, which shows that Ni deposits under B_⊥ promote columnar grain growth, while B_‖ favors lateral, compact structures. Furthermore, moderate temperature (55 °C) in the case of using B_⊥ produced finer grains and smoother surfaces compared to other temperatures in the same direction, enhancing the catalytic performance for HER. Electrochemical techniques, including linear sweep voltammetry (LSV) and chronoamperometry, were employed to evaluate the catalytic performance for HER in 1 M NaOH and the adsorption–desorption process, respectively. The results suggest that efficient HER performance is associated with balanced hydrogen adsorption and desorption behavior. The Ni deposit at 55 °C under (B_⊥) exhibited the lowest overpotential (−215 mV) compared to the deposits at 45 °C and 65 °C under the same magnetic field direction, indicating superior overall HER performance. This performance is attributed to balanced hydrogen adsorption–desorption behavior despite the relatively high Tafel slope value (298 mV·dec⁻¹). However, the lowest Tafel slope among the whole samples prepared under both (B_⊥) and (B_‖) was found to be (219 mV·dec⁻¹), reflecting faster kinetics, which was obtained for the sample deposited at 45 °C under (B_‖). Full article

Per- and polyfluoroalkyl substances (PFASs) in fluorinated firefighting wastewater (FFW), which are difficult to remediate using conventional technologies, represent a critical environmental hazard due to the extreme persistence and bioaccumulation potential of soil–groundwater systems. Niobium-supported boron-doped diamond (BDD) anodes were synthesized by microwave plasma chemical vapor deposition, and their performance in the electrochemical advanced oxidation processes (EAOPs) of FFW were systematically investigated. Under optimized conditions (100 mM Na₂SO₄ electrolyte with 100 mM peroxymonosulfate (PMS), current density of 33.3 mA/cm², pH = 6), the BDD anode achieved near-complete mineralization, with 92.5% total organic carbon (TOC) removal and significant defluorination (77.5% F⁻ release) within 240 min in simulated FFW-contaminated groundwater. For FFW-contaminated soil remediation, 90.2% TOC removal and 41.6% defluorination were achieved after 720 min under optimal treatment (water-to-soil ratio of 20:1). Quenching experiments and electron paramagnetic resonance (EPR) tests revealed that hydroxyl radicals (·OH) and singlet oxygen (¹O₂) were the predominant reactive species. Liquid chromatography–mass spectrometry/mass spectrometry (LC-MS/MS) analysis indicated that PFASs were removed by shortened carbon chains, ultimately mineralizing to CO₂ and F⁻. Toxicity assessment using Vibrio fischeri luminescence demonstrated a reduction in toxicity (from 99.8% to 20.9%), confirming the effective detoxification of BDD-based EAOPs. This work establishes BDD-based EAOPs as a promising technology for eliminating PFASs in groundwater and soil, offering theoretical insights into EAOPs and engineering solutions for PFAS remediation. Full article

This study aims to investigate the effects of graphene oxide-modified titanium dioxide nanotube (TNT-GO) coatings on the biological behavior of Schwann cells and to evaluate their potential applications in dental implant surface modification and peripheral nerve regeneration. Titanium dioxide nanotubes (TNTs) were prepared by anodic oxidation, and graphene oxide (GO) was deposited on their surfaces by electrochemical deposition. The surface morphology and physicochemical properties were characterized by scanning electron microscopy (SEM), Raman spectroscopy, atomic force microscopy, X-ray diffraction, and contact angle measurements. The viability, proliferation, and adhesion of Schwann cells were assessed by cell counting kit-8 assay, live/dead staining, and SEM observation. The expression levels of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) were evaluated by immunofluorescence staining and real-time reverse-transcriptase polymerase chain reaction. The results indicated that TNT-GO surface significantly improved surface hydrophilicity and biocompatibility. Compared with the Ti and TNT groups, Schwann cells on TNT-GO surfaces exhibited enhanced proliferation, better spreading morphology, and significantly increased expression levels of NGF and GDNF. Overall, TNT-GO effectively promotes Schwann cell proliferation, adhesion, and neurotrophic factor secretion, suggesting its potential as a novel surface modification strategy to promote peri-implant nerve regeneration and improve osseoperception. Full article

A combined pretreatment strategy involving alkaline chemical polishing and silane electrodeposition was proposed for regulating the surface state of aluminum foil and the formation of etched tunnels during DC tunnel etching. Electrochemical measurements and morphological characterization were used to evaluate the effects of this pretreatment on surface electrochemical activity and etched tunnel structure. The results showed that appropriate alkaline chemical polishing facilitated the removal of rolling-induced surface relief, improved the uniformity of surface electrochemical activity, and favored the uniform deposition of the silane film. In contrast, excessive polishing generated surface pits during the polishing process, and these preformed pits subsequently promoted tunnel merging during DC tunnel etching. Under the optimal processing conditions, the combined pretreatment significantly improved the distribution uniformity and dimensional consistency of etched tunnels and suppressed tunnel merging. Under the present testing conditions, the specific capacitance increased from 0.386 to 0.509 μF cm⁻², corresponding to an improvement of approximately 31.9%. This work provides an effective approach for optimizing etched tunnel structure and improving the capacitance-related performance of aluminum capacitor foil. Full article

Chromium nitride (CrN) can be used as a coating material deposited via physical vapour deposition (PVD), thereby improving the corrosion and wear resistance of the substrate. However, this level of corrosion protection may not be sufficient in an aggressive corrosion environment. The coatings often contain intrinsic microstructural defects, such as microcraters, which can serve as pathways for the corrosive medium to reach the substrate, thereby initiating and promoting corrosion. In this study, the influence of parameters on the formation of a TiO₂ layer using the ALD technique was investigated. In particular, the work focused on assessing the effectiveness of the TiO₂ layer as a sealing barrier for CrN coatings (PVD) applied to austenitic 316L steel. The TiO₂ ALD coatings were produced at a constant temperature of 200 °C with a varying number of cycles, ranging from 200 to 1000 cycles. Structural investigations were carried out using scanning electron microscopy SEM and atomic force microscopy. Electrochemical properties were investigated using a potentiodynamic test and electrochemical impedance spectroscopy (EIS) in a 3.5% NaCl solution. SEM observations indicate that the morphology of the hybrid coatings is strongly influenced by the number of ALD cycles. The TiO₂ layer conformally reproduces the underlying PVD topography while progressively sealing the coating by filling intrinsic defects and discontinuities. Hybrid coatings (PVD/ALD) with titanium oxide deposited at 500 ALD cycles were found to have the best corrosion resistance. The polarisation resistance for these coatings was nearly four times higher than that of both the single PVD (CrN) coating and the uncoated stainless steel 316L substrate. At the same time, the corrosion current density was several times lower than that of the reference systems. The corrosion mechanisms were investigated by observing the surfaces of the samples after corrosion testing using SEM. Abrasion resistance tests using the pin-on-disc method and adhesion tests (scratch tests) were also performed, which showed that appropriate optimisation of the layer architecture in the PVD/ALD hybrid system significantly improves its tribological durability, interlayer stability, and adhesion to the substrate. Full article

Over the next decade, advanced lithium-based secondary batteries will require high-performance anodes to achieve superior energy density and cycling stability. In this work, anatase titanium dioxide nanotube arrays (TiO₂ NTs) are fabricated on ultrathin Ti paper through anodization and subsequently thermal annealing. An urchin-like 2H-MoS₂ coating is subsequently deposited onto the TiO₂ NTs substrate through magnetic sputtering, constructing a self-supported hierarchical architecture without any additives. Electrochemical characterizations demonstrate that the MoS₂/TiO₂ NTs/Ti composite exhibits lower charge transfer resistance, enhanced rate capability, and improved cycling stability compared with bare TiO₂ NTs/Ti and worm-like MoS₂/Ti control groups. Structural analysis and density functional theory calculations further confirm that the strong interfacial interaction between MoS₂ and TiO₂ effectively stabilizes interfacial integrity during repeated cycling. Upon leveraging tunable geometric structure and mass loadings, this study offers a facile route for developing various types of advanced lithium-based secondary batteries. Full article