Search Results (6,018)

This paper provides a systematic review of urushiol-based antibacterial coatings for lacquer art applications, focusing on three key dimensions: molecular mechanisms, durability, and safety. Natural lacquer films form a dense three-dimensional network through laccase-catalyzed oxidative cross-linking, endowing them with excellent mechanical properties and corrosion resistance, while the catechol structure in urushiol confers broad-spectrum antibacterial potential. The article elaborates on the synergistic antibacterial mechanisms of urushiol, including covalent reactions with bacterial proteins via quinone intermediates, induction of oxidative stress, and metal ion chelation. It also reveals the dynamic change pattern of coating antibacterial activity over time, characterized by “high initial efficiency- gradual mid-term decline—long-term stabilization,” a process influenced collectively by side-chain unsaturation, degree of curing, and environmental factors such as temperature, humidity, and light exposure. From an application perspective, this review examines modification approaches such as silver/titanium dioxide composite systems, structurally regulated sustained-release strategies, and anti-adhesion surface designs, while pointing out current limitations in artistic compatibility, long-term durability, and safety assessment. Particularly in scenarios involving food contact and cultural heritage preservation, migration risks from unreacted urushiol monomers and metal nanoparticles, as well as the inherent sensitization potential of urushiol, remain critical challenges for safe application. Accordingly, this paper proposes the establishment of a holistic research framework covering “material design–process control–performance evaluation” and advocates for the development of functional coating systems with low migration, high biocompatibility, and preserved aesthetic value. Such advances are essential to promote the sustainable development and safe application of urushiol-based antibacterial coatings in fields such as cultural heritage conservation, daily-use utensils, and high-end decorative arts. Full article

cBN-reinforced particle Ti-based composite coatings were deposited by high-speed laser cladding technology to enhance the wear resistance of Ti alloy. In this work, the influence of Ag addition on the microstructure and tribological behavior was systematically investigated. The microstructure and phase composition of the coatings were characterized using SEM/EDS and XRD. And the microhardness and tribological performance of coatings with Ag addition were assessed from room temperature up to 500 °C. The results show that the solidification process evolves with different Ag content. At lower Ag concentrations, Ag dissolves in the Ti-based solid solution, whereas higher Ag concentrations lead to the precipitation of Ag and Ag-Ti intermetallic. Due to the solid-solution strengthening effect and the formation of high-hardness intermetallic phases, the hardness of the coating increases with increasing Ag content. However, excessive Ag addition (>2.5 wt.%) results in a decrease in hardness. Tribological tests reveal that the friction coefficient and wear volume at room temperature decrease with increasing Ag content. With 10 wt.% Ag added, the friction coefficient of the coating decreases by 15% to 0.56, and the wear volume reduces by 28%, with the wear mechanism evolving from adhesive and fatigue wear to oxidative wear. At elevated temperatures (300 °C–500 °C), the friction-reducing effect is further enhanced due to the “sweating” of Ag and the formation of an oxide film, leading to reductions in the friction coefficient of 18%, 13%, and 7% at 300 °C, 400 °C, and 500 °C, respectively, for coatings with 5 wt.% Ag compared to coatings without Ag. Moreover, the formation of hard phases improves the coating’s high-temperature softening resistance and wear resistance property, as evidenced by an 85% reduction in wear volume at 500 °C for coatings containing 5 wt.% Ag. Full article

EPDM is widely used as the polymer matrix for solid rocket motor (SRM) internal thermal protection because of its low density, chemical inertness, and ability to form carbonaceous residue. Practical performance is frequently limited by weak char integrity and barrier properties, char oxidation, mechanical stripping in gas-dynamic flow, and by the poor comparability of published results due to non-uniform test conditions and reporting. This review systematizes studies on 0D nanofillers in EPDM ablatives and harmonizes the key metrics, including linear and mass ablation rates (LAR, MAR), back-face temperature (T_back), and solid residue yield. The major 0D additives-nSiO₂, nTiO₂, nZnO, and carbon black (CB) are compared, and their dominant mechanisms are summarized: degradation-layer structuring, reduced gas permeability, thermo-oxidative stabilization, and effects on vulcanization. Several studies report larger improvements for hybrid systems, where CB enhances char cohesion and retention, while oxide nanoparticles improve barrier performance and resistance to oxidation. Finally, an application-oriented selection matrix is proposed that accounts for thermal protection efficiency, processability, agglomeration limits, and density penalties to support EPDM coating design and improve comparability. Full article

Magnetron sputtering serves as a key method for fabricating functional thin films used in transparent film heaters. However, as heater designs become more intricate, achieving uniform film deposition on nonrectangular areas induces localized overheating owing to current density crowding, compromising long-term reliability of the device. To address this limitation, a simulation-assisted design and fabrication strategy is presented to realize a uniform temperature profile through the precise regulation of the sheet resistance distribution of the film. Initially, an electrothermal-coupled finite element model was established using COMSOL Multiphysics to inversely determine the spatial gradient of sheet resistance required for achieving a uniform thermal distribution. Subsequently, a custom-designed mesh shadow mask was used to locally adjust the flux of indium tin oxide (ITO) sputtered particles, enabling the establishment of a relationship between the mask’s aperture geometry and the resulting particle deposition profile. The magnetic field and plasma simulations were integrated to model particle transport and design a specialized gradient aperture-based shadow mask, enabling the deposition of an ITO film with a controlled sheet resistance gradient in a single magnetron sputtering step. Experimental results demonstrated that the proposed method decreased the maximum temperature variation by 8.25 °C and reduced the standard deviation of the surface temperature by 82.1% at an average temperature of 45 °C within a defined nonrectangular heating region, demonstrating a substantial improvement in temperature uniformity relative to conventional uniform coating processes. Full article

In this study, we present a new approach for detecting carbon dioxide based on the voltammetric behavior of selected pH indicators in a deep eutectic solvent (DES). The sensing strategy exploits the electrochemical oxidation potentials of acid–base indicators, in contrast to their conventional use in spectrophotometric analyses. For this purpose, a screen-printed carbon electrode (SPCE) coated with a thin film of DES containing an acid–base indicator was employed. This approach takes advantage of the unique properties of DESs, which make them safe and appealing electrolytes for gas sensing applications. It also exploits the behavior of acid–base indicators, which can exist in protonated or deprotonated forms with distinct oxidation potentials; the electron-rich basic form oxidizes at a lower potential than its protonated counterpart. Phenol Red (PR), Bromocresol Purple (BCP), and Bromothymol Blue (BTB) were investigated, and their voltammetric behavior was studied in different pH buffers as well as in reline DES. The pH dependence of their oxidation potential was used as the analytical parameter, varying in response to the concentration of acidic species in the gas phase. The proposed strategy was evaluated by performing CO₂ measurements, achieving limits of detection (LOD) and quantification (LOQ) of 2083 and 6875 ppm, respectively. The same approach was then applied to monitor food freshness via CO₂ detection, with results comparing favorably to nondispersive infrared (NDIR) methods for carbon dioxide analysis. Full article

Achieving environmentally friendly, green, and non-toxic marine antifouling has long been a development goal of the modern coatings industry. However, in complex marine environments, non-toxic or low-toxic antifouling coatings often have a significantly reduced service life. Therefore, achieving stable antifouling performance on a low-toxic basis has always been a goal in this industry. By using fluorocarbon resin with low surface energy and spraying a well-mixed blend of alkaline earth metal oil-absorbing nanowires and nano zinc oxide particles that is under high pressure, half-embedded into the resin, and infiltrated with alkanes, the antifouling mechanism of these coatings is achieved by the slow release of oily components, creating a long-lasting liquid–liquid interface to separate biofouling from the coating. Thanks to this antifouling mechanism, the sample maintains a water contact angle of 100–110° for 42 days in static seawater, achieves over 98% resistance to bacterial adhesion, and reaches 99.9% resistance to protein and algae adhesion. This study provides a novel and promising solution for the strict implementation of low-toxic and harmless antifouling. Full article

Per- and polyfluoroalkyl substances (PFASs) are persistent and mobile contaminants of global concern, and, while granular activated carbon (GAC) is widely used for their removal, it is limited by the high regeneration and disposal costs. This study investigates surface-modified clinoptilolite zeolites as low-cost and thermally regenerable alternatives to GAC for PFAS removal from water. Natural clinoptilolite was modified through acid washing, ion exchange with Fe³⁺ or La³⁺, grafting with aminosilane (APTES) or hydrophobic silane (DTMS), dual APTES + DTMS grafting, and graphene oxide coating. The adsorption performance was evaluated for perfluorooctanoic acid (PFOA, C8) and perfluorobutanoic acid (PFBA, C4) at 100 µg L⁻¹ in single- and mixed-solute systems, with an additional high-concentration PFOA test (1 mg L⁻¹). PFAS concentrations were quantified by liquid chromatography–tandem mass spectrometry (LC–MS/MS) using a SCIEX 7500 QTRAP system coupled to a Waters ACQUITY UPLC I-Class. Raw zeolite showed limited PFOA removal (4%), whereas dual-functionalized APTES + DTMS zeolites achieved up to 93% removal, comparable to GAC (97%) and superior to single-silane or metal-exchanged variants. At lower concentrations, modified zeolites effectively removed PFOA but showed limited PFBA removal (<25%), highlighting ongoing challenges for short-chain PFASs. Overall, the results demonstrate that dual-functionalized clinoptilolite zeolites represent a promising and scalable platform for PFAS remediation, particularly for mid- to long-chain compounds, provided that strategies for enhancing short-chain PFAS binding are further developed. Full article

Recent advancements in nanotechnology have led to the development of multifunctional nanoplatforms that significantly enhance both cancer diagnosis and treatment. Gold-based nanoparticles, such as peptide-functionalized nanostructures and PEG-coated nanorods, offer improved tumor targeting, multimodal imaging (including photoacoustic and fluorescence), and effective photothermal therapy. Similarly, ultrafine iron oxide nanoprobes provide superior tumor imaging, while silver-based nanoparticles exhibit rapid systemic circulation, near-infrared fluorescence, and powerful photothermal properties. Titanium-based nanoplatforms enable a combination of therapies and advanced imaging methods. On the therapeutic side, polymeric nanoparticles (PNPs), silica-based platforms, PEG-based nanoparticles, and graphene oxide-based systems each offer unique advantages for targeted drug delivery and theranostics. PNPs, with tunable size, shape, and surface chemistry, enable controlled drug release and reduced side effects, while silica-based nanoplatforms improve tumor targeting and imaging. PEG-based nanoparticles enhance drug release and tumor penetration, and graphene oxide-based systems facilitate subcellular targeting and synergistic therapies. Collectively, these innovations are paving the way for more efficient, precise, and safer cancer therapies, leading to improved clinical outcomes. Full article

This work provides a systematic experimental study for the electrochemical desalination of saline water using an electrospun permselective polyvinylidene difluoride (PVDF) membrane. Several nano additives were initially screened during membrane development; however, only the materials that demonstrated stable dispersion, reproducible membrane formation, and consistent electrochemical behaviour, namely graphene oxide (GO) and carbon nanotubes (CNTs) were selected for full analysis in this study. Accordingly, the study focuses on pure PVDF, PVDF/GO, and PVDF/CNTs membranes integrated with an alternating Ag/AgCl electrode system. The silver electrode is prepared by spray-coating of silver nanoparticles on high surface carbon cloth, whereas the AgCl electrode was prepared electrochemically from the Ag electrode using a three-electrode electrochemical cell. The electrochemical behaviour of various modified electrodes (bare carbon cloth, Ag/carbon cloth, Ag/nafion/carbon black/PVDF, and Ag/nafion/carbon cloth) was evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and X-Ray Diffraction (XRD). The electrode prepared using Nafion and PVDF as binders with carbon black as conductive additive exhibited the highest current response and lowest charge-transfer resistance. When coupled with this optimized electrode, the PVDF/GO membrane delivered the best desalination performance, achieving an ion removal efficiency of 68%, a salt adsorption capacity (SAC) of 775.40 mg/g, and a specific energy consumption (SEC) of 16.17 kJ/mole values superior to those reported in the literature. Full article

This article reports on how the length of the alkyl chain influences the morphological properties of thiol-stabilized silver nanoparticles (Ag NPs) and their subsequent effects on the performance and durability of proton exchange membrane fuel cells (PEMFCs). We synthesized thiol-stabilized Ag NPs by varying the alkyl chain length: 1-hexane thiol (C6), 1-octanethiol (C8), 1-decanethiol (C10), 1-dodecanethiol (C12), and 1-tetradecanethiol (C14), which we achieved using the two–phase Brust–Schiffrin method. X-ray Diffraction (XRD) patterns confirm the formation of crystalline Ag NPs. A morphological study conducted using a Transmission Electron Microscope (TEM) demonstrated that smaller alkyl chain length thiols (C6, C8, and C10) tend to coalesce, while C12 shows better uniformity with no agglomeration. C14 produces larger nanoparticles. A distinct pressure-area isotherm was observed when Ag NPs were spread at the water/air interface of a Langmuir–Blodgett (LB) trough. After obtaining the monolayer formation pressure range, we coated the Nafion 117 membrane of a polymer electrolyte membrane fuel cell with these nanoparticles to form monolayers of different Ag NPs (C6, C8, C12, C14) at various surface pressures (2 mN/m, 6 mN/m and 10 mN/m). Maximum power output enhancement was observed for C12, while other nanoparticles (C6, C8, C10, C14) did not exhibit noticeable power enhancement for PEMFCs. C12 Ag NPs deposited at surface pressure 6 mN/m give maximum power density increase (26.5%) at the fuel cell test station. In addition, we examined the carbon monoxide (CO) resistance test by mixing 0.1% CO with hydrogen (H2), and C12 Ag NPs showed the highest resistance to CO poisoning. However, no enhancement in power or CO tolerance was observed when C12 Ag NPs were coated by spray coating. These outcomes showcase that alkyl chain length plays a critical role in controlling the size and distribution of thiol-stabilized nanoparticles, which eventually has a direct impact on the performance and CO resistance of PEMFCs when applied to polymer electrolyte (Nafion 117). In addition, surface pressure during monolayer formation controls the distribution of Ag NPs (the distance between nanoparticles at the membrane interface), which is necessary to achieve catalytic activity for power improvement and to prevent platinum (Pt) poisoning by CO oxidation at ambient conditions. Full article

The role of the long-period stacking ordered (LPSO) phase on the microstructure and corrosion properties of micro-arc oxidation (MAO) ceramic coatings was systematically investigated in this study. Optical microscopy and scanning electron microscopy (SEM) were employed to characterize the MAO coatings, while their corrosion behavior was evaluated through electrochemical measurements and immersion tests in a 3.5 wt.% NaCl solution. The results reveal that the sample containing the LPSO phase exhibited an increased coating thickness. However, the coating formed on the LPSO-containing Mg alloy presented a highly porous morphology with numerous large micropores. This defective microstructure compromised the protective barrier function of the ceramic layer, ultimately resulting in inferior corrosion resistance compared to coatings on its LPSO-free counterparts. Full article

A novel ternary nanocomposite, comprising reduced graphene oxide/polyaniline/gadolinium oxide (RGO-PANI-Gd₂O₃), was successfully synthesized using the Hummers method, followed by in situ emulsion polymerization of polyaniline. The final composite was produced by hydrothermally adding gadolinium nitrate. The composite was subjected to a systematic analysis that included optical, microstructural, physical, and Raman spectroscopic analysis, as well as current-voltage (J-V) measurements. The morphology of this composite material was investigated using scanning electron microscopy (SEM). The addition of Gd₂O₃ nanoparticles decreases the band gap energy from 3.5 eV (PANI) to 2.7 eV (RGO-PANI-Gd₂O₃). The UV–Vis spectra revealed a redshift in the π-π* transition peak from 318 nm (PANI) to 346 nm, indicating increased conjugation length and synergistic effects. This eco-friendly material has excellent catalytic activity for triiodide reduction. The manufactured counter-electrode (CE) demonstrated remarkable transparency and conversion efficiency comparable to platinum, with a current density of 11.7 mA·cm⁻² versus 8.2 mA·cm⁻² for platinum. Under simulated solar light (AM 1.5 G, 100 mW·cm⁻²), the RGO-PANI-Gd₂O₃ based nanocomposite CE achieved an excellent 4.3% photo conversion efficiency. These findings indicate that RGO-PANI-Gd₂O₃ nanocomposites have potential as efficient, platinum-free counter electrodes in dye-sensitized solar cells (DSSCs). Full article

To elucidate the effects of TiO₂ nanoparticles on the microstructure and corrosion resistance of micro-arc oxidation (MAO) coatings formed on 6061 aluminum alloy, MAO coatings were prepared in a silicate-based electrolyte with varying TiO₂ nanoparticle concentrations. The coating structure and properties were evaluated using a coating thickness gauge, surface profilometer, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and an electrochemical workstation. The results show that, with increasing TiO₂ content, both coating thickness and surface roughness gradually increase, while the surface porosity first decreases and then increases. An appropriate amount of TiO₂ effectively lowers the surface porosity and enhances coating compactness. The T₁ condition exhibited the least precipitation of corrosion products during immersion tests and thus the best corrosion resistance. Compared to the untreated 6061 aluminum alloy substrate, the optimized coating demonstrated a reduction in corrosion current density (J_corr) by more than one order of magnitude, reaching 1.127 × 10⁻⁶ A·cm⁻², while its polarization resistance (R_p) increased by over one order of magnitude, attaining 3.558 × 10⁴ Ω·cm². Furthermore, relative to the TiO₂-free T₀ coating, the J_corr of the optimized coating was further reduced by approximately 2.5 times, with its R_p enhanced by about 2.3 times. XRD analysis indicated that the MAO coatings primarily consist of α-Al₂O₃ and γ- Al₂O₃. This study provides theoretical and experimental support for the application of TiO₂ nanoparticles in MAO processes. Full article

To optimize the aerodynamic performance of the aircraft across its entire cross-section, wing shape control must be maintained based on flight operating conditions. A high-temperature flexible textile composite, which is the key to achieving the deformation of an aircraft wing, is urgently required in the deformable structure of high-speed aircraft. In this work, a novel type of flexible textile composite with enhanced temperature resistance was fabricated by plain-woven carbon fibers coated with silicone rubber. The material testing was carried out in a wind tunnel to simulate both the harsh temperature field distribution and the mechanical loads caused by aerodynamic forces under the flight profile. For the first time, temperatures exceeding 1000 °C were attained on the windward side of an aircraft wing with a peak recorded temperature of 1600 °C. The failure mechanisms of the flexible composites are revealed, and the thermal stability of the composites is evaluated. The results show that the significant tensile anisotropy in the flexible composites is along different off-axis angles, and the failure modes also change with the off-axis angle. The material does not show significant high-temperature oxidation ablation under thermo-mechanical coupling. This work reveals that under the triple action of such high temperatures, stress caused by wing surface tensioning, and the mechanical load caused by aerodynamic forces, the failure mechanism of the flexible textile composite is dominated by the mechanical load at high temperatures rather than by thermal instability, as is conventionally claimed. Full article

Poly(3,4-ethylenedioxythiophene)–polystyrene sulfonate (PEDOT:PSS) is widely used to fabricate conductive organic coatings for electrodes in electrophysiology. As these devices move toward clinical translation, establishing sterilization methods that preserve their functional properties is essential. Ethylene oxide (EtO) is routinely used for sterilizing heat- and moisture-sensitive medical devices due to its high penetration efficiency and low thermal load. However, the absence of systematic studies evaluating its impact on PEDOT:PSS raises concerns about the compatibility of EtO sterilization with organic electrophysiology interfaces. Here, we report the first comprehensive evaluation of EtO sterilization on PEDOT:PSS electrodes electrochemically deposited onto cortical interfaces designed for intraoperative monitoring and stimulation. EtO exposure induced only minimal changes in surface topography, with no detectable alteration of the electrical or electrochemical performance of the electrodes. Impedance spectroscopy, cyclic voltammetry, and charge-injection capacity measurements all revealed that EtO-treated electrodes retained properties comparable to untreated controls. Moreover, EtO-sterilized PEDOT:PSS coatings demonstrated robust long-term stability under accelerated lifetime testing, exhibiting negligible degradation over extended operation. These findings demonstrate that EtO sterilization is fully compatible with PEDOT:PSS-based bioelectronic interfaces and constitutes a viable pathway toward their safe and effective integration into clinical electrophysiology. This work represents an important step toward translating organic conducting polymer technologies into real-world biomedical applications. Full article