Search Results (6,426)

Background: Soft tissue stability around dental implant abutments is critical for maintaining a functional peri-implant seal. Yellow anodization is used to improve the aesthetic and surface characteristics of titanium abutments, yet its epithelial effects under more physiologically relevant 3D conditions remain insufficiently explored. Objective: To develop a 3D bioprinted in vitro peri-implant mucosa model and to compare epithelial cell responses on yellow anodized versus turned titanium abutment surfaces. Methods: Commercial Grade 5 (Ti6Al4V) titanium abutments were anodized and compared with turned controls. A collagen-based 3D bioprinted “collar-like” construct incorporating YD-38 epithelial cells was fabricated using a custom holder system to simulate peri-implant mucosal contact. Samples were cultured for 14 and 21 days. Cell distribution and morphology were assessed by optical microscopy and HE staining, while cytoskeletal organization was evaluated by TRITC-phalloidin/Hoechst staining and confocal microscopy. Quantitative fluorescence analysis was performed at 21 days. Results: Both surfaces supported epithelial coverage in the 3D environment. Anodized specimens showed more pronounced actin cytoskeletal organization and the presence of actin-rich, filamentous cellular extensions compared with turned controls. Quantitative image analysis demonstrated significantly higher TRITC-phalloidin signal intensity at 21 days on anodized samples (p < 0.001). Conclusions: Within the limitations of a 3D epithelial in vitro model using YD-38 cells, yellow anodization was associated with enhanced epithelial cytoskeletal organization compared with turned titanium. The presented 3D bioprinted platform may serve as a practical in vitro tool for screening abutment surface modifications relevant to peri-implant soft tissue integration. Full article

Hard carbon is widely recognized as a viable anode candidate for sodium-ion batteries (SIBs) owing to its electrochemical advantages, yet simultaneously enhancing specific capacity and rate capability, arising from insufficient plateau capacity, remains a long-standing challenge. Herein, we present a strategy for fabricating ZnCl₂-modified hard carbon (HCMZ-X) using waste macadamia shells and ZnCl₂ as a multifunctional structural modifier through a facile high-temperature carbonization. This approach effectively expands the graphite interlayer spacing to 0.394 nm, reduces microcrystalline size, and induces abundant closed pores, synergistically improving sodium-ion storage kinetics within the hard carbon framework. Mechanistic investigations confirm an “adsorption-intercalation-filling” storage mechanism. Hence, the optimized HCMZ-3 delivers a high reversible capacity of 382.05 mAh g⁻¹ at 0.05 A g⁻¹, with the plateau region contributing approximately 70%, significantly outperforming that of unmodified hard carbon (262.64 mAh g⁻¹). Remarkably, it achieves stable rate performance, delivering 190 mAh g⁻¹ at 1 A g⁻¹, along with excellent cycling stability, retaining over 90% after 500 cycles. By rational pore-structure modulation rather than excessive surface activation, this cost-effective method utilizing agricultural waste and ZnCl₂ dual-functional modification partially alleviates the intrinsic energy-density limitation of hard carbon anodes, advancing the development of high-performance, eco-friendly anodes for scalable energy storage systems. Full article

Type II collagen is a primary fibrillar component of articular cartilage, and its early degradation is a key biomarker of joint-degenerative disorders such as osteoarthritis, rheumatoid arthritis, gout, etc. Reliable detection at low concentrations remains challenging due to limited assay accessibility, complex analytical procedures, and nonspecific responses in multicomponent biological matrices. This research reports the development of a Molecularly Imprinted Polymer (MIP)–based electrochemical sensor engineered for the selective recognition of type II collagen. A series of monomer formulations were evaluated, and the 1AAM:2VP composition produced a well-defined imprinted layer on screen-printed carbon electrodes, yielding the highest electrochemical sensitivity and linearity. The optimized sensor exhibited strong anodic and cathodic responses proportional to increasing collagen concentrations, with a calibration slope corresponding to an R² value of 0.9394. Minimal signal interference was observed, confirming high molecular selectivity. The limit of detection (LOD) was calculated to be approximately 0.065 µg/mL. These characteristics demonstrate that the proposed MIP sensor provides a low-cost, accessible, and highly selective analytical platform suitable for early-stage cartilage degeneration monitoring. Full article

Low-voltage primary batteries broadly power small electronics used in health, biomedical, and wearable applications. These devices are generally more sensitive to volumetric capacity than gravimetric capacity. The current state-of-the-art button battery is Zn-Ag₂O, where contributors that limit volumetric capacity include the incorporation of inactive materials in the electrode microstructure such as gelling agents, binders, and conductive additives. Herein, cathode materials of CuO and FeS₂ will be described for small form factor coin/button cells. When paired with Li metal anodes, the operating voltage is similar to Zn-Ag₂O. The key innovation is that they will be processed into all-active-material (AAM) electrode architectures, where the electrodes will comprise only electroactive materials and pores that are filled with electrolyte during cell fabrication. The AAM architecture significantly enhanced electroactive material volume utilization, and thus volumetric capacity. FeS₂ and CuO were processed into AAM electrodes under various processing conditions, and Li-FeS₂ and Li-CuO primary batteries were fabricated and evaluated. At the cell level, volumetric capacity of 1300 mAh cm⁻³ was achieved, and in a button cell form factor 395/927, nearly 100 mAh was delivered, which compares favorably with commercially available options, which typically range from 27 to 55 mAh. Full article

Direct ethanol fuel cells (DEFCs) have gained considerable attention as promising power sources for sustainable energy conversion due to their high energy density, low toxicity, and renewable ethanol feedstock. However, the sluggish ethanol oxidation reaction (EOR) kinetics and the formation of strongly adsorbed intermediates (e.g., CO*, CH_x*) severely hinder catalytic efficiency and durability. Rhodium (Rh)-based catalysts stand out for their balanced intermediate adsorption, efficient C–C bond cleavage, and superior CO tolerance arising from their unique electronic structure. This review summarizes recent advances in Rh-based EOR catalysts, including monometallic Rh nanostructures, Rh-based alloys, and Rh–support composites. The effects of morphology, alloying, and metal–support interactions on activity, selectivity, and stability are discussed in detail. Strategies for structural and electronic regulation—such as nanoscale design, alloying modulation and interfacial engineering—are highlighted to enhance catalytic performance. Finally, current challenges and future directions are outlined, emphasizing the need for Rh-based catalysts with high activity, selectivity and stability, integrating in situ characterization with theoretical modeling. This work provides insights into the structure–activity relationships of Rh-based catalysts and guidance for designing efficient and durable anode catalysts for practical DEFC applications. Full article

The Mixed-Conduction Model for oxide films is used to quantitatively interpret in situ electrochemical and ex situ surface analytical results on the corrosion of AISI 316L (an internal reactor material) and Alloy 690 (a steam generator tube material) in small modular reactor primary coolant with the addition of soluble Zn. The model parameters of alloy oxidation and corrosion release are estimated with the time of exposure up to 168 h and anodic polarization potential (up to −0.25 V vs. standard hydrogen electrode) using fitting of the transfer function to experimental impedance spectra. Model parameters of individual alloy constituents are estimated by fitting of the model equations to the atomic fraction profiles of respective elements in the formed oxide obtained by Glow-Discharge Optical Emission Spectroscopy (GDOES). Conclusions on the effect of Zn addition on film growth and cation release processes in boron-free SMR coolant are drawn and future research directions are outlined. Full article

Electrocatalytic CO₂ reduction is a promising approach to mitigate rising atmospheric CO₂ levels while converting CO₂ into valuable products such as CH₄. Conversion into other useful substances further expands its potential applications. However, the efficiency of the CO₂ reduction reaction (CO₂RR) is strongly influenced by device geometry and CO₂ mass transfer in the electrolyte. In this work, we present and evaluate microchannel electrocatalytic devices consisting of a porous Cu cathode and a Pt anode, fabricated via metal-assisted chemical etching (MACE). The porous surfaces generated through MACE enhanced reaction activity. To study the impact of the distance between electrodes, several devices with different channel heights were fabricated and tested. The device with the highest CH₄ selectivity had a narrow inter-electrode gap of 50 μm and achieved a Faradaic efficiency of 56 ± 11% at an applied potential of −5 V versus an Ag/AgCl reference electrode. This efficiency was considerably higher than that of the device with larger inter-electrode gaps (300 and 480 μm). This reduced efficiency in the larger channel was attributed to limited CO₂ availability at the cathode surface. Bubble visualization experiments further demonstrated that the electrolyte flow rate had a strong impact on supplied CO₂ bubble morphology and mass transfer. At a flow rate of 0.75 mL/min, smaller CO₂ bubbles were formed, increasing the gas–liquid interfacial area and thereby enhancing CO₂ dissolution into the electrolyte. These results underline the critical role of electrode gap design and bubble dynamics in optimizing microchannel electrocatalytic devices for efficient CO₂RR. Full article

This work investigates the corrosion behavior of 18%Ni high-strength steel (00Ni18Co-8Mo5TiAl, solution-treated at 820 °C for 3 h and aged at 480 °C for 3 h) in NaCl solutions with 1%, 3.5%, and 6% chloride ions, as well as chloride ions’ effect on passive film properties. The corrosion process was systematically studied via chemical immersion tests (GB/T 17897-1999, 144 h, solution-to-sample contact area ratio 20:1) and electrochemical methods, including EIS (frequency range: 100 kHz–0.01 Hz) and Tafel polarization curves (scan rate: 10 mV/min). Passive film evolution was analyzed via Mott–Schottky curves (fixed frequency: 1000 Hz, scanning potential: −1 V to 1 V vs. SCE). Microstructural observations show the steel exhibits pitting corrosion in chloride environments, with corrosion products transforming from loose outer α-FeOOH/γ-FeOOH to dense inner Fe₃O₄/β-FeOOH. These dense products inhibit anodic reactions. Electrochemical results reveal polarization resistance decreases and corrosion current density rises with increasing chloride concentration. Mott–Schottky curves indicate that flat band potential increases from −0.2177 V to −0.1258 V with rising chloride concentration, increasing point defects in the passive film and weakening its self-healing ability. Full article

A well-defined heterojunction and tailored interface of the photocathode are desired to facilitate the efficient separation and transfer of photogenerated charge carriers for photoelectrochemical (PEC) hydrogen generation. Herein, optimized Z-scheme heterojunction (denoted as F-COF/TiO₂) photoelectrodes were designed and fabricated by solvothermally growing a F-substituted imine-linked covalent organic framework (F-COF) from 1,3,5-tris(3-fluoro-4-formylphenyl)benzene and 1,4-diaminobenzene on the surface of anodized TiO₂ nanotubes for enhanced PEC hydrogen evolution. The F-COF/TiO₂ heterojunction with photo-deposited Pt species as cocatalysts (Pt@F-COF/TiO₂) revealed higher cathodic photocurrent density, decreased interfacial resistance, and improved onset potential due to the improved charge separation and transfer efficiency at the interface. Both the internal electric field between F-COF and TiO₂, as well as the enhanced photophysical nature of F-COF films, contributed to the efficient interfacial charge separation and transfer. The photo-deposited Pt species and applied bias voltage also demonstrated a synergetic effect on facilitating charge separation and transfer for hydrogen production. The Pt@F-COF/TiO₂ photoelectrode featured an improved PEC hydrogen evolution rate under AM 1.5G simulated sunlight irradiation and a durable PEC hydrogen evolution performance. This study provides valuable insights into the design of heterojunction-based photoelectrodes for efficient solar-driven hydrogen production for sustainable energy applications. Full article

Zinc-based alloys are promising candidates for biodegradable implant applications; however, their rapid initial corrosion and limited cytocompatibility remain major challenges. In this study, a Zn-Ca-P layer in a form of parascholzite (CaZn₂(PO₄)₂·2H₂O) was prepared on a Zn-0.8Mg-0.2Sr alloy via anodic oxidation followed by short-time biomimetic calcium–phosphate deposition. The formation mechanism, corrosion behaviour, and preliminary biological response of the modified surface were systematically investigated. The Zn-Ca-P layer formed a compact and crystalline phosphate layer that significantly altered the corrosion response of the zinc substrate in Leibovitz L-15 medium containing foetal bovine serum. Electrochemical measurements revealed a pronounced improvement in corrosion resistance and a transition from rapid active dissolution to a controlled, ion-exchange-driven degradation mechanism. The moderate solubility of parascholzite enabled the gradual release of Zn²⁺ and Ca²⁺ ions while maintaining surface stability during immersion. Preliminary cell adhesion experiments demonstrated a clear enhancement of cytocompatibility for the Zn-Ca-P-layer-coated samples, where cells readily adhered and spread, in contrast to the bare alloy surface, which showed lower cell attachment. The improved biological response is attributed to the phosphate-rich surface chemistry, favourable surface morphology, and moderated corrosion behaviour. Overall, the parascholzite-like layer provides an effective strategy with which to regulate both corrosion and early cell–material interactions of zinc-based biodegradable alloys, highlighting its potential for temporary biomedical implant applications. Full article

Chlorinated solvents such as vinyl chloride (VC) and trichloroethylene (TCE) represent a persistent threat to groundwater-derived drinking-water supplies, including riverbank filtration well fields in alluvial aquifers. This work presents a laboratory-scale evaluation of an electrochemical barrier concept for targeted VC and TCE removal performed using synthetic groundwater representative of a riverbank filtration setting in the Danube River basin. Experiments were conducted in a covered batch reactor equipped with Ti/IrO₂–RuO₂ mixed-metal-oxide anodes and Ti cathodes, systematically varying current intensity (10–60 mA), treatment time (0–60 min), active anode surface area (12–48 cm²), and inter-electrode distance (0.5–2.5 cm). At 60 mA, VC and TCE removals of 97% and 95%, respectively, were achieved within 20 min, while prolonged treatment to 60 min increased removal to about 99% for VC and 98.5% for TCE. Multivariate analysis (PCA) and correlation assessment identified applied current as the dominant control parameter, particularly for TCE removal, whereas electrode configuration and spacing played secondary roles within the investigated range. For the most cost-effective treatments meeting Serbian drinking-water criteria, estimated electricity costs were 0.39 €/m³ for VC and 0.10 €/m³ for TCE. Overall, the results demonstrate the technical feasibility and promising cost-effectiveness of electrochemical barriers as a proactive measure to protect riverbank filtration systems from future VC and TCE contamination n urban environments, while highlighting the need for follow-up studies on by-product formation and long-term performance. Full article

In recent years, green hydrogen production via water electrolysis driven by renewable energy sources has garnered increasingly significant attention. Among the various water electrolysis technologies, proton-exchange membrane water electrolysis (PEMWE) distinguishes itself owing to the unique advantages, including the compact architecture, high efficiency, rapid dynamic response, and high purity of the generated hydrogen. The membrane electrode assembly (MEA) serves as the core component of a PEM electrolyzer. And only a high-performance and stable MEA can provide a reliable platform for investigating the mass transport behavior within the porous transport layer (PTL). In this study, the MEA fabrication method was optimized by varying the ionomer-to-carbon (I/C) ratio, coating strategy, and anode Ir mass loading. As a result, the cell voltage was reduced from 1.679 V to 1.645 V at 1.0 A cm⁻², with a small degradation of 1.3% over 70 h of operation. Based on the optimized MEA, the effects of the structure and porosity of PTL on the mass transport behavior were further analyzed. After the PTL parameter optimization, the cell voltage was further reduced to 1.630 V at 1.0 A cm⁻², while a high-speed camera captured bubble dynamics in real time, showing the fast detachment of small oxygen bubbles. The integrated electrochemical and visualization results provide a useful guideline to designing both MEA and PTL for efficient PEMWE. Full article

Ice accumulation on power transmission lines poses serious threats to operational safety and can lead to substantial social and economic impacts. While various anti-icing coatings have been investigated, their performance is often limited by the effectiveness and durability of anti-icing. Slippery lubricant-infused porous surfaces (SLIPSs) have shown remarkable anti-icing properties and durability, aided by their lubricant-infused and self-healing capability. In this study, SLIPSs were successfully fabricated on aluminum substrates using a two-step anodization process. The effects of the anodizing parameter of the current density on pore diameter and depth at each stage were systematically investigated. Compared to untreated aluminum and superhydrophobic coatings (SHCs), SLIPSs presented good anti-icing properties. First, at −6 °C, droplets slid off the surface completely within 4340.5 ms without pinning, indicating sustained droplet-shedding capability. It also significantly delayed ice formation, extending the freezing time to 80 min—eight times longer than that of the untreated surface. Moreover, the SLIPSs also exhibited ultra-low ice adhesion, with an initial strength of only 6.93 kPa. Meanwhile, after 100 frosting–defrosting cycles, SLIPSs could still maintain low ice adhesion strength (<20 kPa). The prepared SLIPS with a Y-shaped pore structure demonstrates good potential for anti-icing. Full article

This study presents a straightforward strategy for producing novel, effective and inexpensive functional non-noble metal-supported carbon materials made from abundant natural biomass. These materials offer a cost-effective alternative to noble metals for the oxidation of hydrazine (HzOR) and demonstrate the potential for widespread adoption of green, energy-saving hydrazine-based technologies in energy applications. Highly efficient and cost-effective iron (Fe) and manganese–iron (MnFe)-supported nitrogen-doped carbon (N–C) materials were developed using hydrothermal synthesis. Meanwhile, the N–C material was obtained from biomass—birch-wood chips—using hydrothermal carbonisation (HTC), followed by activation and nitrogen doping of the resulting hydrochar. The morphology, structure, and composition of the MnFe, MnFe/N–C, and Fe/N–C catalysts were determined using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray spectroscopy (EDS). The activity of the catalysts for HzOR in an alkaline medium was evaluated using cyclic voltammetry (CV). Depositing MnFe particles onto N–C was shown to significantly enhance electrocatalytic activity for HzOR compared to the Fe/N–C catalyst and especially to the MnFe particles catalyst in terms of highly developed porous structure, which offers the largest surface area, lowest onset potential, and highest current density response, resulting in the strongest catalytic activity. These results suggest that the MnFe/N–C catalyst could be a highly promising anode material for HzOR in direct hydrazine fuel cells (DHFCs). Full article