Surfaces, Volume 8, Issue 3 (September 2025) – 28 articles

The behavior of S and Cs during the alternate adsorption of each adsorbate on the Ni(100) surface is studied at room and elevated temperatures by means of low-energy electron diffraction (LEED), Auger electron spectroscopy (AES), thermal desorption spectroscopy (TDS) and work function (WF) measurements. For Cs deposition on the S-covered Ni(100) surface, the presence of sulfur increases the binding energy and the maximum amount of adsorbed cesium, as happens with other alkalis too. The first Cs overlayer is disordered, while the second strongly interacts with S with a tendency toward a Cs_xS_y surface compound formation. This interaction causes the gradual demetallization of the Cs overlayer with the increasing S coverage in the underlayer. When the Cs_xS_y stoicheometry is complete, however, subsequent Cs deposition forms an independent rather metallic overlayer. When the sulfated covers the surface, S(0.5ML)/Ni(100) is preheated to 1100 K, the S-Ni bond strengthens and S-Cs interaction correspondingly weakens to a degree that the S underlayer retains a periodic structure on the Ni substrate. This behavior indicates that the preheated S/Ni(100) surface is passivated to a degree against Cs with reduced mobility of sulfur adatoms. Differently, when S is adsorbed on the Cs-covered Ni(100) surface at room temperature, sulfur adatoms diffuse underneath the Cs overlayer to interact with the nickel substrate and form the same structural phases as on a clean surface. During that process, the sticking coefficient of sulfur remains constant regardless of the amount of pre-deposited cesium. The presence of Cs, however, increases the amount of S that can be deposited on the Ni substrate, probably in favor of the Cs_xS_y compound formation, which demetallizes the surface independent of the sequence of adsorption. Full article

Oily wastewater is a critical environmental concern, and the high costs and fouling of conventional membranes drive the search for low-cost, efficient alternatives. This study evaluates surface-modified quartz particles for oil–water separation, focusing on hydrophilic and hydrophobic coatings. Quartz samples underwent washing, hydrophobic coating, and hydrophilic coating, with morphological and elemental changes assessed using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS). Oil and grease (O&G) content was determined via the EPA 1664 method under high-solids conditions. The untreated oil–water mixture contained 142,955.9 mg/L O&G. Hydrophilic-coated quartz achieved the greatest reduction, producing water with only 751.3 mg/L O&G, indicating excellent oil rejection and water selectivity. Washed quartz performed similarly at 837.1 mg/L. Hydrophobic-coated quartz, while yielding higher residual oil in water (64,198.9 mg/L), demonstrated strong oil affinity, making it more suitable for oil recovery applications. Raw quartz, tested without heavy oil loading, showed a baseline of 13.4 mg/L. These results confirm that surface engineering of quartz enables tunable separation properties, where hydrophilic surfaces favor water purification and hydrophobic surfaces enhance oil capture. The findings provide a pathway for scalable, cost-effective, and application-specific oily wastewater treatment solutions. Full article

Wood and bamboo products with log-term carbon storage, less energy consumption, and CO₂ emission face the challenge of fungal infection. Their antifungal property can be enhanced by Cu-based nanoparticles. Herein, Cu₂O-coated Cu (Cu₂O@Cu) aggregates were grown in situ on the surface of pine wood (PW), beech wood (BW), oak wood (OW), and bamboo via vacuum impregnation. Morphology, crystalline structure, elemental ratio, and chemical state of Cu₂O@Cu and Cu₂O@Cu-loaded specimens were characterized. Uniformly distributed agglomerates composed of Cu₂O@Cu exhibited an average size of 2 μm (Cu₂O@Cu-loaded PW and Cu₂O@Cu-loaded BW) and several hundred nanometers (Cu₂O@Cu-loaded OW and Cu₂O@Cu-loaded bamboo) on the surfaces. A strong mold resistance for Aspergillus niger was achieved after cultivating Cu₂O@Cu-loaded specimens for 28 days. Infection values were grade 0 for Cu₂O@Cu-loaded PW and grade 1 for Cu₂O@Cu-loaded BW, Cu₂O@Cu-loaded OW, and Cu₂O@Cu-loaded bamboo (p < 0.05), which were significantly better than those of pristine specimens (grade 2 for PW and grade 4 for BW, OW and bamboo). A low leaching rate of 5.23–7.81% with three repetitions presented a monotonically positive relation with the loading atomic content of Cu (12.6–27.1 at. %), demonstrating an excellent stability of Cu₂O@Cu-loaded specimens. This study highlighted the potential of Cu-based preservatives in the field of wood and bamboo preservation. Full article

W/Si multilayer mirrors are a promising candidate for soft X-ray applications at wavelengths below 2.4 nm. However, their optical performance is strongly affected by interface roughness and interlayer mixing, which limits reflectivity. One approach to improving interface quality is the application of BIAS voltage during deposition. In this study, W/Si multilayer mirrors with bilayer thickness of ~1.5 nm and 100 bilayers were fabricated using DC magnetron sputtering, with ion assistance of 75 V, 100 V, and 200 V applied during the deposition of silicon layers. Grazing incidence X-ray reflectivity (GIXR) measurements at Cu Kα (λ = 0.154 nm) showed that applying BIAS ≤ 100 V reduced interface roughness and increased reflectivity, with a maximum effect observed at 75 V. In contrast, at 200 V, strong diffusion intermixing reduced the bilayer thickness to 1.29 nm and nearly eliminated reflectivity. Soft X-ray reflectivity measurements at λ ~ 1.5 nm confirmed that ion assistance improved optical performance, increasing mirror reflectivity from ~1% (BIAS = 0 V) to ~2.3% (BIAS = 75 V). Atomic force microscopy (AFM) measurements also demonstrated a reduction in surface roughness from 0.22 nm to 0.11 nm due to using ion assistance. These results indicate that moderate ion assistance (<100 V) can enhance the optical quality of W/Si multilayer mirrors by reducing interface roughness, while excessive BIAS (>100 V) leads to diffusion intermixing and optical degradation. The novelty of this work lies in the direct application and variation in BIAS voltage during Si-layer growth, enabling detailed investigation of its influence on interface roughness and reflectivity. This approach provides a simple and effective tool for optimizing the performance of W/Si multilayer mirrors for soft X-ray applications. Full article

The integration of emulsion gels in 3D food printing has emerged as a promising strategy to enhance both the structural fidelity and functional performance of printed foods. Emulsion gels, composed of proteins, polysaccharides, lipids, and their complexes, can provide tunable rheological and mechanical properties suitable for extrusion and shape retention. This review explores the formulation strategies, including phase behavior (O/W, W/O, and double emulsions); stabilization methods; and post-printing treatments, such as enzymatic, ionic, and thermal crosslinking. Advanced techniques, including ultrasound and high-pressure homogenization, are highlighted for improving gel network formation and retention of active compounds. Functional applications are addressed, with a focus on meat analogs, bioactive delivery systems, and personalized nutrition. Furthermore, the role of the oil content, interfacial engineering, and protein–polysaccharide interactions in improving print precision and post-processing performance is emphasized. Despite notable advances, challenges remain in scalability, regulatory compliance, and optimization of print parameters. The integration of artificial intelligence can also provide promising advances for smart design, predictive modeling, and automation of the 3D food printing workflow. Full article

To study the adsorption of lanthanide (Ln) atoms on graphene containing a Stone–Wales defect, we used a cluster model (SWG) and performed calculations at the PBE-D2/DNP level of the density functional theory. Our previous study, where the above combination was complemented with the ECP pseudopotentials, was only partially successful due to the impossibility of calculating terbium-containing systems and a serious error found for the SWG complex with dysprosium. In the present study we employed the DSPP pseudopotentials and completely eliminated the latter two failures. We analyzed the optimized geometries of the full series of fifteen SWG + Ln complexes, along with their formation energies and electronic parameters, such as frontier orbital energies, atomic charges, and spins. In many regards, the two series of calculations show qualitatively similar features, such as roughly M-shaped curves of the adsorption energies and trends in the changes in charge and spin of the adsorbed Ln atoms, as well as the spin density plots. However, the quantitative results can differ significantly. For most characteristics we found no evident correlation with the lanthanide contraction. The only dataset where this phenomenon apparently manifests itself (albeit to a limited and irregular degree) is the changes in the closest Ln^…C approaches. Full article

Adhesion of cell membranes is relevant to many biological processes and arises from the specific binding of membrane-anchored receptor proteins to their ligands present in the apposing membrane. Here, we employ a statistical–mechanical model and perform Monte Carlo simulations to study a system of adhered membranes in which the receptor and ligand proteins exhibit affinity for association with so-called lipid rafts, which are fluctuating nanoscale molecular clusters enriched in sphingolipid and cholesterol. We focus on equilibrium properties of the adhered membranes in the mixed phase, where both the membrane-anchored proteins and lipid rafts are distributed more-or-less uniformly within the membranes. Our simulation results show that lateral attraction between lipid rafts enhances the receptor–ligand binding, affecting the adhesion of the membranes. On the other hand, the receptor–ligand binding causes lipid rafts to be distributed less uniformly within the membranes and, simultaneously, leads to an increased co-localization of the membrane-anchored proteins with lipid rafts. We quantify and discuss all these effects, providing a detailed picture of the complex interplay between the adhesion of the membranes and the lateral distribution of the membrane-anchored proteins and lipid rafts. Our results broaden the understanding of the physical mechanisms that determine the supra-molecular organization of lipid rafts and membrane receptors in cell membranes. This understanding may help to elucidate how lipid rafts function in biological processes such as cell signaling and immune responses. Full article

Organic and pharmaceutical pollution of water is a serious problem, particularly when it comes to drinking and groundwater. Although some evaluations indicate that these pollutants are unlikely to be at current exposure levels, they are often detected in aquatic systems and can be harmful to human health. Organic contaminants include hazardous micropollutants, aromatic phenols, pesticides, etc. Pharmaceutical contaminants are sulfamethoxazole, diclofenac, doxycycline, amoxicillin, trimethoprim, ciprofloxacin, norfloxacin, lipid regulators, nonsteroidal anti-inflammatory drugs (NSAIDs), hormones, antidepressants, etc. Hydrogel adsorbents’ distinct structural, chemical, and environmentally benign qualities make them a potential and successful option for environmental remediation, especially in wastewater treatment. In the search for clean water resources, they are an important instrument because of their reusability and capacity to be customized for certain contaminants, such as organic and pharmaceutical pollutants. This review focusses on the present state, adsorption sites and surfaces, different adsorption mechanisms, and the prospects and scope of improvement of effective hydrogels for eliminating dangerous aqueous organic and pharmaceutical contaminants. It offers a thorough summary of the area, highlighting its facets and potential paths forward. Full article

Surface modification of carbon fibers (CFs) is a critical step in preparing carbon fiber-reinforced composites. This study developed a continuous experimental process that integrates electrochemical anodic oxidation and chemical vapor deposition to fabricate carbon nanotubes/carbon fiber (CNTs/CF) reinforcements. The effects of temperature and hydrogen flow rate during CNT growth on the resulting reinforcements were systematically investigated. The surface morphology and mechanical properties of the modified materials were characterized using scanning electron microscopy, Raman spectroscopy, and single-fiber tensile testing. Employing an Fe_0.5Ni_0.5 bimetallic catalyst under optimized conditions (550 °C, H₂ flow rate: 0.45 mol/min, C₂H₂ flow rate: 0.30 mol/min), the resulting reinforcement exhibited an 8.7% increase in tensile strength compared to as-received CF. Full article

Although the exponential increase in photovoltaic installations does contribute to mitigating climate change, it has posed the problem of photovoltaic (PV) residue. As PV panels contain strategic metals, their recovery has become a priority. This paper therefore employs a mesoporous carbon impregnated with P507 extractant as adsorbent to selectively recover gallium and indium from solutions simulating the leachate of end-of-life CIGS (Copper Indium Gallium Selenide) cells in a fixed-bed. The previous batch results obtained in our lab show that both metals can be selectively separated by simply adjusting the initial pH, with large adsorption capacities (44.97 mg/g for gallium and 34.24 mg/g for indium). The obtained breakthrough curves were fitted to the Thomas, Yan, Yoon, and HSDM (Homogeneous Surface Diffusion Model) models using a simulation program developed in Python 3.12 obtaining good results in all cases (R² > 0.9). The estimated parameters were used to predict the experimental breakthrough curve for a different experiment that had not been used for parameter estimation, being the best predictive results the obtained with the HSDM. This is logical, given that unlike the other three models, it is mechanistic. Full article

Zirconia (ZrO₂) ceramics and composites have attracted much attention in aerospace, biomedical and energy fields due to their high hardness, high wear resistance, excellent chemical stability and biocompatibility. However, the brittleness of ceramics and the high cost of molds have made it difficult for traditional processing techniques to manufacture complex structural and functional components efficiently. Additive manufacturing technology has successfully overcome these challenges by optimizing the preparation process and improving production efficiency. Among them, vat photopolymeriztion (VPP) has been demonstrated to offer distinct advantages, including high precision, high efficiency and low cost. It provides a novel approach to the preparation of zirconia ceramics. VPP preparation of zirconia ceramics and composites needs to consider various steps such as slurry preparation, structural design and printing, debinding and sintering. This review introduces common VPP technologies related to zirconia ceramics and summarizes the factors affecting the rheological and curing properties of zirconia slurry, in order to provide researchers with a reference for studying VPP preparation of zirconia. The current optimization methods for light-curing zirconia slurry formulations are focused on, and common methods for surface modification and optimization of slurry composition and solid loading are introduced. The influencing factors of the printing process are summarized, and the current research on surface texturing of VPP preparation and the influence of printing parameters on the performance and accuracy of the components are introduced. The effects of debinding/sintering processes on cured zirconia ceramics are also summarized. The applications of VPP zirconia ceramics and composites are proposed, especially for their use in biomedical and energy applications. Full article

The array of regular square pyramid microstructures with zero-spacing features is an ideal structural topology for building superhydrophobic functional surfaces due to its excellent anti-wetting performance and low surface adhesion properties. In the framework of existing studies, this microstructured array is usually considered to exist only in two typical wetting states, the stable Cassie state and the Wenzel state. In this study, a third type of wetting state, the incomplete Wenzel state, was discovered for the first time using experimental characterization, and the evolution mechanism of this new wetting state was revealed based on critical contact angle theory and numerical simulation. It is revealed that the faces and edges of the square pyramid microstructures exhibit different tilting angles, and this unique geometrical design endows them with dual critical contact angles. When the intrinsic contact angle of the microstructure is between the critical contact angles for the edges and faces, the wetting behavior of the droplet contact line in the directions parallel to the edges and faces will generate spontaneous and non-spontaneous competition effects, which lead to the formation of the incomplete Wenzel state. The dual-critical-angle theoretical model constructed in this study provides a new perspective for improving the theoretical system of wetting dynamics on pyramid arrays. Full article

In this study, we present a comprehensive theoretical analysis of modifications in the physical and chemical properties of MoSe₂ upon the introduction of substitutional transition metal impurities, specifically, Ti, V, Cr, Fe, Co, Ni, Cu, W, Pd, and Pt. Wet systematically calculated the adsorption enthalpies for various representative analytes, including O₂, H₂, CO, CO₂, H₂O, NO₂, formaldehyde, and ethanol, and further evaluated their free energies across a range of temperatures. By employing the formula for probabilities, we accounted for the competition among molecules for active adsorption sites during simultaneous adsorption events. Our findings underscore the importance of integrating temperature effects and competitive adsorption dynamics to predict the performance of highly selective sensors accurately. Additionally, we investigated the influence of temperature and analyte concentration on sensor performance by analyzing the saturation of active sites for specific scenarios using Langmuir sorption theory. Building on our calculated adsorption energies, we screened the catalytic potential of doped MoSe₂ for CO₂-to-methanol conversion reactions. This paper also examines the correlations between the electronic structure of active sites and their associated sensing and catalytic capabilities, offering insights that can inform the design of advanced materials for sensors and catalytic applications. Full article

The photon spin Hall effect (PSHE) arises from the spin–orbit interaction of light. Metasurfaces enable precise control over the PSHE through their influence. Using electromagnetic simulations as its foundation, this work engineers a metal–insulator–metal (MIM) metasurface for generating vortex beams in the near-infrared band, targeting enhanced modulation of the PSHE. Electromagnetic simulations embed vanadium dioxide (VO₂)—a thermally responsive phase-change material—within the MIM metasurface architecture. Numerical evidence confirms that harnessing VO₂’s insulator–metal-transition-mediated optical switching dynamically tailors spin-dependent splitting in the illuminated MIM-VO₂ hybrid, thereby achieving a significant amplification of the PSHE displacement. Electromagnetic simulations determine the reflection coefficients for both VO₂ phase states in the MIM-VO₂ structure. Computed spin displacements under vortex beam incidence reveal that VO₂’s phase transition couples to the MIM’s top metal and dielectric layers, modifying reflection coefficients and producing phase-dependent PSHE displacements. The simulation results show that the displacement change of the PSHE before and after the phase transition of VO₂ reaches 954.7 µm, achieving a significant improvement compared with the traditional layered structure. The dynamic modulation mechanism of the PSHE based on the thermal–optical effect has been successfully verified. Full article

This study proposes a laser texturing method to optimize adhesion and minimize residual stresses in CVD diamond films deposited on tungsten carbide (WC-Co). WC-5.8 wt% Co substrates were textured with quadrangular pyramidal patterns (35 µm) using a 1064 nm nanosecond-pulsed laser, followed by chemical treatment (Murakami’s solution + aqua regia) to remove surface cobalt. Diamond films were grown via HFCVD and characterized by Raman spectroscopy, EDS, and Rockwell indentation. The results demonstrate that pyramidal texturing increased the surface area by a factor of 58, promoting effective mechanical interlocking and reducing compressive stresses to −1.4 GPa. Indentation tests revealed suppression of interfacial cracks, with propagation paths deflected toward textured regions. The pyramidal geometry exhibited superior cutting post-deposition cooling time for stress relief from 3 to 1 h. These findings highlight the potential of laser texturing for high-performance machining tool applications. Full article

Efficient detection of toxic and flammable vapors remains a major technological challenge, especially for environmental and industrial applications. This paper reports on the fabrication technology and gas-sensing properties of nanostructured Ga₂O₃/GaS_0.98Se_0.02. The β-Ga₂O₃ nanowires/nanoribbons with inclusions of Ga₂S₃ and Ga₂Se₃ microcrystallites were obtained by thermal treatment of GaS_0.98Se_0.02 slabs in air enriched with water vapors. The microstructure, crystalline quality, and elemental composition of the obtained samples were investigated using electron microscopy, X-ray diffraction, and Raman spectroscopy. The obtained structures show promising results as active elements in gas sensor applications. Vapors of methanol (CH₃OH), ethanol (C₂H₅OH), and acetone (CH₃-CO-CH₃) were successfully detected using the nanostructured samples. The electrical signal for gas detection was enhanced under UV light irradiation. The saturation time of the sensor depends on the intensity of the UV radiation beam. Full article

We present a buffer-pH-modulated electrokinetic concentration strategy in MEMS microchannels that harnesses simple pH shifts to neutralize and charge proteins, reversibly “pausing” them at a planar electric-gate electrode by tuning to their isoelectric point (pI) and mobilizing them with slight pH offsets under an applied field. This synergistic coupling of dynamic pH control and electrode-gated focusing, which requires only buffer composition changes, enables rapid and tunable protein capture and release across diverse channel geometries for lab-on-chip, preparative, and point-of-care diagnostics. Moreover, it dovetails with established MEMS biomedical platforms ranging from diagnostics to drug delivery and microsurgery to gene and cell-manipulation devices. Future work on tailored electrode coatings and optimized channel profiles will further boost selectivity, speed, and integration in sub-100 µm MEMS devices. Full article

Aluminum nitride (AlN) thin films were deposited on SiO₂ substrates by RF-magnetron sputtering at varying powers (110–140 W) and subsequently subjected to thermal annealing at 450 °C under nitrogen atmosphere. A comprehensive multi-technique investigation—including X-ray reflectometry (XRR), X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), optical profilometry, spectroscopic ellipsometry (SE), and electrical measurements—was performed to explore the physical structure, morphology, and optical and electrical properties of the films. The analysis of the film structure by XRR revealed that increasing sputtering power resulted in thicker, denser AlN layers, while thermal treatment promoted densification by reducing density gradients but also induced surface roughening and the formation of island-like morphologies. Optical studies confirmed excellent transparency (>80% transmittance in the near-infrared region) and demonstrated the tunability of the refractive index with sputtering power, critical for optoelectronic applications. The electrical characterization of Au/AlN/Al sandwich structures revealed a transition from Ohmic to trap-controlled space charge limited current (SCLC) behavior under forward bias—a transport mechanism frequently present in a material with very low mobility, such as AlN—while Schottky conduction dominated under reverse bias. The systematic correlation between deposition parameters, thermal treatment, and the resulting physical properties offers valuable pathways to engineer AlN thin films for next-generation optoelectronic and high-frequency device applications. Full article

Bioactive glasses are known for their surface reactivity and ability to bond with bone tissue through the formation of hydroxyapatite. This study investigates the effects of substituting ultrapure water with natural geothermal waters from the Azores in the sol–gel synthesis of 45S5 and MgO-modified bioglasses. Using high-resolution X-ray photoelectron spectroscopy (XPS), we examined how the mineral composition of the waters influenced the chemical environment and network connectivity of the glass surface. The presence of trace ions, such as Mg²⁺, Sr²⁺, Zn²⁺, and B³⁺, altered the silicate structure, as evidenced by binding energy shifts and peak deconvolution in O 1s, Si 2p, P 2p, Ca 2p, and Na 1s spectra. Thermal treatment further promoted polymerization and reduced hydroxylation. Our findings suggest that mineral-rich waters act as functional agents, modulating the reactivity and structure of bioactive glass surfaces in eco-sustainable synthesis routes. Full article

Microbial extracellular polymeric substances (EPSs) are emerging as sustainable alternatives to conventional corrosion inhibitors due to their eco-friendly nature, biodegradability, and functional versatility. Secreted by diverse microorganisms including bacteria, fungi, archaea, and algae, EPSs are composed mainly of polysaccharides, proteins, lipids, and nucleic acids. These biopolymers, chiefly polysaccharides and proteins, are accountable for surface corrosion prevention through biofilm formation, allowing microbial survival and promoting their environmental adaptation. Usually, EPS-mediated corrosion inhibitions can take place via different mechanisms: protective film formation, metal ions chelation, electrochemical property alteration, and synergy with inorganic inhibitors. Even though efficacious EPS corrosion prevention has been demonstrated in several former studies, the application of such microbial inhibitors remains, so far, a controversial topic due to the variability in their composition and compatibility toward diverse metal surfaces. Thus, this review outlines the microbial origins, biochemical properties, and inhibition mechanisms of EPSs, emphasizing their advantages and challenges in industrial applications. Advances in synthetic biology, nanotechnology, and machine learning are also highlighted and could provide new opportunities to enhance EPS production and functionality. Therefore, the adoption of EPS-based corrosion inhibitors represents a promising strategy for environmentally sustainable corrosion control. Full article

It is widely recognized that fine surface structures found in nature contribute to surface functionality, and studies on the design of functional materials based on biomimetics have been actively conducted. In this study, polymer thin films with hierarchically ordered surface structure were prepared by combining both nanoimprinting using anodically oxidized porous alumina (AAO) as a template and surface-initiated atom transfer radical polymerization (SI-ATRP). To prepare such polymer films, we designed a new copolymer (poly{[2-(4-methyl-2-oxo-2H-chromen-7-yloxy)ethyl methacrylate]-co-[2-(2-bromo-2-methylpropionyloxy)ethyl methacrylate]}; poly(MCMA-co-HEMABr)) with coumarin moieties and α-haloester moieties in the pendants. The MCMA repeating units function to fix the pillar structure by photodimerization, and the HEMABr ones act as the polymerization initiation sites for SI-ATRP on the pillar surfaces. Surface structures consisting of vertically oriented multiple pillars were fabricated on the spin-coated poly(MCMA-co-HEMABr) thin films by nanoimprinting using an AAO template. Then, the coumarin moieties inside each pillar were crosslinked by UV light irradiation to fix the pillar structure. SEM observation confirmed that the internally crosslinked pillar structures were maintained even when immersed in organic solvents such as 1,2-dichloroethane and anisole, which are employed as solvents under SI-ATRP conditions. Finally, poly(2,2,2-trifluoroethyl methacrylate) and poly(N-isopropylacrylamide) chains were grafted onto the thin film by SI-ATRP, respectively, to prepare the hierarchically ordered surface structure. Furthermore, in this study, the surface properties as well as the thermoresponsive hydrophilic/hydrophobic switching of the obtained polymer films were investigated. The surface morphology and chemistry of the films with and without pillar structures were compared, especially the interfacial properties expressed as wettability. Grafting poly(TFEMA) increased the static contact angle for both flat and pillar films, and the con-tact angle of the pillar film surface increased from 104° for the flat film sample to 112°, suggesting the contribution of the pillar structure. Meanwhile, the pillar film surface grafted with poly(NIPAM) brought about a significant change in wettability when changing the temperature between 22 °C and 38 °C. Full article

Understanding strain behavior near grain boundaries is critical for controlling structural distortions and oxygen vacancy migration in perovskite oxides. However, conventional techniques often lack the spatial resolution needed to analyze phase and domain evolution at the nanoscale. In this paper, polarization-dependent second-harmonic generation (SHG) imaging is employed as a tool to probe local symmetry breaking and complex domain structures in the vicinity of a low-angle grain boundary of SrTiO₃ (STO) bicrystals. We show that the anisotropic strain introduced by a tilted grain boundary produces strong local distortions, leading to the coexistence of tetragonal and rhombohedral domains. By analyzing SHG intensity and variations in the second-order nonlinear optical susceptibility, we map the distribution of strain fields and domain configurations near the boundary. In pristine samples, the grain boundary acts as a localized source of strain accumulation and symmetry breaking, while in samples subjected to intentional electrical stressing, the SHG response becomes broader and more uniform, suggesting strain relaxation. This work highlights SHG imaging as a powerful technique for visualizing grain-boundary-driven structural changes, with broad implications for the design of strain-engineered functional oxide devices. Full article

This study presents the influence of pH control agents and pH value on the physical properties of ZnO thin films obtained by chemical bath deposition. ZnO thin films were synthesized on glass substrates using precursor solutions of different pHs prepared from two bases: sodium hydroxide (NaOH) and ammonia (NH₃). The effect of pH values on the morphological, structural, and optical properties of ZnO thin films was investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and UV–Visible spectroscopy. XRD results showed that all the synthesized ZnO thin films are polycrystalline and crystallize in a hexagonal wurtzite structure. The crystallite size, calculated using the Debye–Scherrer formula, varied from 10.50 nm to 11.69 nm for ZnO thin films obtained with NH₃ and from 20.79 nm to 27.76 nm for those obtained with NaOH. FTIR analysis confirmed the presence of functional groups. SEM images indicated that not only the base but also the pH affects the morphology of the films, giving rise to different granular shapes. Overall, the ZnO thin films obtained with NaOH looked more mesoporous compared to those obtained with NH₃. Optical characterization results showed that whatever the base used, the pH of the precursor solution affected the ZnO thin film transmittance. Films synthesized with NH₃ exhibited the best transmittance (80%) at pH 8.5, while the best transmittance (81%) of films synthesized with NaOH was obtained at pH 8 in the visible region. Based on optical and morphological properties, ZnO films obtained from NH₃ at pH 8.5 are found to be more suitable as photoanodes in dye-sensitized solar cells. Full article

To promote the optimization of the anti-friction and anti-wear behavior of lightweight TiAl alloys, γ-TiAl-10 wt.% Ag self-lubricating composites were fabricated, and their mechanical and tribological properties were tested. The results showed that the silver in TiAl-10 wt.% Ag slightly reduced its mechanical properties compared with those of pure TiAl alloys. A silver-enriched lubrication film formed on a wear scar, which was helpful in improving the friction and wear behavior. It was found that a large amount of silver gathered at a wear scar, gradually spread out under the action of the sliding friction force, and then increased the silver distribution areas on the wear scar, leading to the good formation of a silver-rich film. Furthermore, an identification model was established to calculate the specific area η of the silver film. A quantitative relationship indicated that an increase in the Ag distribution area improved the tribological behavior of γ-TiAl-10 wt.% Ag. When the specific area η of a silver-rich film was maintained at 44–51%, the small friction coefficient (almost 0.28) and wear rate (about 2.25 × 10⁻⁴ mm³·N⁻¹·m⁻¹) were well stabilized. This provides a new research method to improve the tribological performance of TiAl-Ag samples. Full article

Electroless silver (Ag) plating has emerged as a simple yet effective surface modification technique, garnering significant attention in consumer electronics and composite materials. This study systematically investigates the influence of glucose dosage on the microstructural refinement of Ag coatings deposited from silver–ammonia solutions onto iron (Fe) particles while also evaluating the oxidation resistance of Ag-plated particles through thermogravimetric analysis. Optimal results were achieved at a silver nitrate concentration of 0.02 mol/L and a glucose concentration of 0.05 mol/L, producing Fe particles with a uniform and dense silver coating featuring an average Ag grain size of 76 nm. The moderate excess glucose played a dual role: facilitating Ag⁺ ion reduction while simultaneously inhibiting the growth of Ag atomic clusters, thereby ensuring microstructural refinement of the silver layer. Notably, the Ag-plated particles demonstrated superior oxidation resistance compared to their uncoated counterparts. These findings highlight the significance of fine-grained electroless Ag plating in developing high-temperature conductive metal particles and optimizing interfacial structures in composite materials. Full article

Thin films of manganese–nickel–cobalt oxide with graphene (G@MNCO) were deposited on copper foam using electrochemical deposition. NiCo₂O₄ is the main phase in these films. As the proportion of graphene in the precursor solution increases, the oxygen vacancies in the samples also increase. The microstructure of these samples evolves into hierarchical vertical flake structures. Cyclic voltammetry measurements conducted within the potential range of 0–1.2 V reveal that the electrode with the highest graphene content achieves the highest specific capacitance, approximately 475 F/g. Furthermore, it exhibits excellent cycling durability, maintaining 95.0% of its initial capacitance after 10,000 cycles. The superior electrochemical performance of the graphene-enhanced, manganese-doped nickel–cobalt oxide electrode is attributed to the synergistic contributions of the hierarchical G@MNCO structure, the three-dimensional Cu foam current collector, and the binder-free fabrication process. These features promote quicker electrolyte ion diffusion into the electrode material and ensure robust adhesion of the active materials to the current collector. Full article

Growing demand for chemically resistant, thermally stable, and anti-icing coatings has intensified interest in boron nitride (BN)-based materials and surface coatings. In this study, BN coatings were developed on mild steel (MS) via chemical vapour deposition (CVD) at 1200 °C for 15, 30, and 60 min, and their structural, surface, and water-repellent characteristics were evaluated. X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy confirmed the successful formation of BN, while water contact angle measurements indicated high hydrophobicity, demonstrating excellent barrier properties. Scanning electron microscopy (SEM) revealed morphological evolution from flower- and needle-like BN structures in the sample placed in the CVD furnace for 15 min to dense, coral-like, and tubular networks in the samples placed for 30 and 60 min. These findings highlight that BN coatings, particularly the one obtained after 30 min of deposition, have a high hydrophobic character following the Cassie–Baxter model and can be used for corrosion resistance and anti-icing on MS, making them ideal for industrial applications requiring long-lasting protection. Full article

Polyaryletherketone (PAEK) polymers inherently exhibit low surface activity, leading to poor adhesive bonding performance when using epoxy-based adhesives. In this study, low-temperature plasma surface modification was conducted on carbon fiber-reinforced polyetherketone ketone (CF/PEKK) composites to investigate the influence of plasma treatment parameters on their lap shear strength. Surface characterization was systematically performed using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and contact angle analysis to evaluate morphological, chemical, and wettability changes induced via plasma treatment. The results demonstrated a significant enhancement in lap shear strength after plasma treatment. Optimal bonding performance was achieved at a treatment speed of 10 mm/s and a nozzle-to-substrate distance of 5 mm, yielding a maximum shear strength of 28.28 MPa, a 238% improvement compared to the untreated control. Notably, the failure mode transitioned from interfacial fracture in the untreated sample to a mixed-mode failure dominated by cohesive failure of the adhesive and substrate. Plasma treatment substantially reduced the contact angle of CF/PEKK, indicating improved surface wettability. SEM micrographs revealed an increased micro-porous texture on the treated surface, which enhanced mechanical interlocking between the composite and adhesive. XPS analysis confirmed compositional alterations, specifically elevated oxygen-containing functional groups on the plasma-treated surface. These modifications facilitated stronger chemical bonding between CF/PEKK and the epoxy resin, thereby validating the efficacy of plasma treatment in optimizing surface chemical activity and adhesion performance. Full article