Search Results (1,352)

Hydrogen energy is a pivotal carrier for achieving carbon neutrality, requiring green and efficient production via water electrolysis. However, the anodic oxygen evolution reaction (OER) involves a sluggish four-electron transfer process, resulting in high overpotentials, while the prohibitive cost and complex preparation of precious metal catalysts impede large-scale commercialization. In this study, we develop a FeCo-based bimetallic deep eutectic solvent (FeCo-DES) as a multifunctional reaction medium for engineering a three-dimensional (3D) coral-like FeOOH-Co₂(OH)₃Cl/NF composite via a mild one-step impregnation approach (70 °C, ambient pressure). The FeCo-DES simultaneously serves as the solvent, metal source, and redox agent, driving the controlled in situ assembly of FeOOH-Co₂(OH)₃Cl hybrids on Ni(OH)₂/NiOOH-coated nickel foam (NF). This hierarchical architecture induces synergistic enhancement through geometric structural effects combined with multi-component electronic interactions. Consequently, the FeOOH-Co₂(OH)₃Cl/NF catalyst achieves a remarkably low overpotential of 197 mV at 100 mA cm⁻² and a Tafel slope of 65.9 mV dec⁻¹, along with 98% current retention over 24 h chronopotentiometry. This study pioneers a DES-mediated strategy for designing robust composite catalysts, establishing a scalable blueprint for high-performance and low-cost OER systems. Full article

The anode assembly, as a key component in the electrolytic aluminum process, is composed of steel claws and aluminum guide rods. The connection quality between the steel claws and guide rods directly affects the current conduction efficiency, energy consumption, and operational stability of equipment. Achieving high-quality joining between the aluminum alloy and steel has become a key process in the preparation of the anode assembly. To join the guide rods and steel claws, this work uses Cold Metal Transfer (CMT) technology to clad aluminum on the steel surface and employs machine vision to detect surface forming defects in the cladding layer. The influence of different currents on the interfacial microstructure and mechanical properties of aluminum alloy cladding on the steel surface was investigated. The results show that increasing the cladding current leads to an increase in the width of the fusion line and grain size and the formation of layered Fe₂Al₅ intermetallic compounds (IMCs) at the interface. As the current increases from 90 A to 110 A, the thickness of the Al-Fe IMC layer increases from 1.46 μm to 2.06 μm. When the current reaches 110 A, the thickness of the interfacial brittle phase is the largest, at 2 ± 0.5 μm. The interfacial region where aluminum and steel are fused has the highest hardness, and the tensile strength first increases and then decreases with the current. The highest tensile strength is 120.45 MPa at 100 A. All the fracture surfaces exhibit a brittle fracture. Full article

The oxygen evolution reaction (OER) plays a central role as an anode in electrocatalytic processes such as energy conversion and storage and the generation of molecular oxygen from the electrolysis of water. Currently, precious metal oxides such as IrO₂ and RuO₂ are recognized as reference OER electrocatalysts with reasonably high activity; however, their widespread use in practical devices has been severely hindered by their high cost and scarcity. It is essential to design alternative OER electrocatalysts made of low-cost and abundant earth elements with significant activity and robustness. We report four new nanocellulose-derived Fe–zeolite nanocomposites, namely Fe/Zeolite@CCNC (1), Fe/Zeolite@CCNF (2), Fe/Zeolite/CNT@CCNC (3), and Fe/Zeolite/CNT@CCNF (4). Two different types of nanocellulose were investigated: nanocellulose nanofibrils and nanocellulose nanocrystals. Characterization with TEM, SEM-EDS, PXRD, and XPS is reported. The nanocomposites exhibited electrocatalytic activity for OER that varies based on the origin of biocarbon and the composition content. The effect of adding carbon nanotubes to the nanocomposites was studied, and an improvement in OER catalysis was observed. The electrochemical double-layer capacitance and electrochemical impedance spectroscopy of the nanocomposites are reported. The nanocomposite 3 exhibited the highest performance, with an onset potential value of 1.654 V and an overpotential of 551 mV, which exceeds the activity of RuO₂ for OER catalysis at 10 mA/cm² in the glassy carbon electrode. A 24 h chronoamperometry study revealed that the catalyst is active for ~2 h under continuous operating conditions. BET surface analysis showed that the crystalline nanocellulose-derived composite exhibited 301.47 m²/g, and the fibril nanocellulose-derived composite exhibited 120.39 m²/g, indicating that the increased nanoporosity of the former contributes to the increase in OER catalysis. Full article

Lithium metal is a promising anode material for next-generation batteries due to its high specific capacity and low density. However, conventional mechanical processing methods are unsuitable due to lithium’s high reactivity and adhesion. Laser cutting offers a non-contact alternative, but photothermal effects can negatively impact the cutting quality and electrochemical performance. This study investigates the influence of pulse duration on the cutting-edge characteristics and electrochemical behavior of laser-cut 20 µm lithium metal on 10 µm copper foils using nanosecond and picosecond laser systems. It was demonstrated that shorter pulse durations significantly reduce the heat-affected zone (HAZ), resulting in improved cutting quality. Electrochemical tests in symmetric Li|Li cells revealed that laser-cut electrodes exhibit enhanced cycling stability compared with mechanically separated anodes, despite the presence of localized dead lithium “reservoirs”. While the overall pulse duration did not show a direct impact on ionic resistance, the characteristics of the cutting edge, particularly the extent of the HAZ, were found to influence the electrochemical performance. Full article

The remarkable advantages of zinc anodes render aqueous zinc-ion batteries (ZIBs) a highly promising energy storage solution. Nevertheless, the uncontrolled growth of zinc dendrites and side reactions pose significant obstacles to the practical application of ZIBs. To address these issues, a straightforward strategy has been proposed, involving the addition of a minute quantity of AgNO₃ to the electrolyte to stabilize zinc anodes. This additive spontaneously forms a hierarchically porous Ag interphase on the zinc anodes, which is characterized by its zinc-affinitive nature. The interphase offers abundant zinc nucleation sites and accommodation space, leading to uniform zinc plating/stripping and enhanced kinetics of zinc deposition/dissolution. Moreover, the chemically inert Ag interphase effectively curtails side reactions by isolating water molecules. Consequently, the incorporation of AgNO₃ enables zinc anodes to undergo cycling for extended periods, such as over 4000 h at a current density of 0.5 mA/cm² with a capacity of 0.5 mAh/cm², and for 450 h at 2 mA/cm² with a capacity of 2 mAh/cm². Full zinc-ion cells equipped with this additive not only demonstrate increased specific capacities but also exhibit significantly improved cycle stability. This research presents a cost-effective and practical approach for the development of reliable zinc anodes for ZIBs. Full article

We developed a novel and portable magnetic nanochannel electrochemical sensor for the sensitive detection of cadmium ions (Cd²⁺), which pose serious risks to food safety and human health. The sensor was fabricated by co-modifying an anodic aluminum oxide (AAO) nanochannel membrane with a composite of glutathione (GSH) and ferric oxide nanoparticles (Fe₃O₄), denoted as GSH@Fe₃O₄. This modified membrane was then integrated with a screen-printed carbon electrode (SPCE) to construct the GSH@Fe₃O₄/GSH@AAO/SPCE sensing platform. The performance of the sensor was evaluated using differential pulse voltammetry (DPV), which demonstrated a strong linear correlation between the peak current response and the concentration of Cd²⁺ in the range of 5–120 μg/L. The calibration equation was I_DPV(μA) = −0.31 + 0.98·C_{Cd²⁺(μg/L)}, with an excellent correlation coefficient (R² = 0.999, n = 3). The calculated limit of detection (LOD) was as low as 0.1 μg/L, indicating the high sensitivity of the system. These results confirm the successful construction of the GSH@Fe₃O₄/GSH@AAO/SPCE portable nanochannel sensor. This innovative sensing platform provides a rapid, sensitive, and user-friendly approach for the on-site monitoring of heavy metal contamination in agricultural products, especially grains. Full article

To improve implant osseointegration while preventing infection, we developed a strontium (Sr)-doped Ti₃C₂T_x MXene coating on titanium, aiming to synergistically enhance bone integration and antibacterial performance. MXene is a family of two-dimensional transition-metal carbides/nitrides whose abundant surface terminations endow high hydrophilicity and bioactivity. The coating was fabricated via anodic electrophoretic deposition (40 V, 2 min) of Ti₃C₂T_x nanosheets, followed by SrCl₂ immersion to incorporate Sr²⁺. The coating morphology, phase composition, chemistry, hydrophilicity, mechanical stability, and Sr²⁺ release were characterized. In vitro bioactivity was assessed with rat bone marrow mesenchymal stem cells (BMSCs)—with respect to viability, proliferation, migration, alkaline phosphatase (ALP) staining, and Alizarin Red S mineralization—while the antibacterial efficacy was evaluated against Staphylococcus aureus (S. aureus) via live/dead staining, colony-forming-unit enumeration, and AlamarBlue assays. The Sr-doped MXene coating formed a uniform lamellar structure, lowered the water-contact angle to ~69°, and sustained Sr²⁺ release (0.36–1.37 ppm). Compared to undoped MXene, MXene/Sr enhanced BMSC proliferation on day 5, migration by 51%, ALP activity and mineralization by 47%, and reduced S. aureus viability by 49% within 24 h. Greater BMSCs activity accelerates early bone integration, whereas rapid bacterial suppression mitigates peri-implant infection—two critical requirements for implant success. Sr-doped Ti₃C₂T_x MXene thus offers a simple, dual-function surface-engineering strategy for dental and orthopedic implants. Full article

The surface topography of the rolls used in skin-pass cold rolling determines the surface finish of rolled sheets. In this sense, work rolls can be intentionally textured to produce certain topographical features on the final sheet surface. The maskless electrochemical texturing method (MECT) is a potential candidate for industrial-scale application due to its reduced texturing cost and time when compared to traditional texturing methods. However, there are few studies in the literature that address the MECT method applied to the topography control of cold rolling work rolls. The present work aims to analyze the viability of surface texturing via MECT of work rolls used in skin-pass cold rolling. In this study, we first investigated how texturing occurs for tool steel using flat textured samples to facilitate the understanding of the dissolution mechanisms involved. In this case, a specially designed texturing chamber was built to texture flat samples extracted from an actual work roll. The results indicated that the anodic dissolution involved in tool steel texturing occurs preferentially in the metallic matrix around the primary carbides. Then, we textured a work roll used in pilot-scale rolling tests, which required the development of a special prototype to texture cylindrical surfaces. After texturing, the texture transfer from the work roll to the sheets was investigated. Rolling tests showed that the work roll surface textured with a dimple pattern generated a pillar-shaped texture pattern on the sheet surface, possibly due to a reverse extrusion mechanism. Full article

The growing demand for high-energy, safe, and sustainable lithium-ion batteries has increased interest in nickel-rich cathode materials and solid-state electrolytes. This study presents a scalable wet-processing method for fabricating composite cathodes for all-solid-state batteries. The cathodes studied herein are high-nickel LiNi_0.90Mn_0.05Co_0.05O₂, NMC955, the sulfide-based electrolyte Li₆PS₅Cl, and alternative binders—polyvinyl alcohol (PVA) and polyisobutylene (PIB)—dispersed in toluene, a non-polar solvent compatible with the electrolyte. After fabrication, the cathodes were characterized using SEM/EDX, sheet resistance, and Hall effect measurements. Electrochemical tests were additionally performed in all-solid-state battery half-cells comprising the synthesized cathodes, lithium metal anodes, and Li₆PS₅Cl as the separator and electrolyte. The results show that both PIB and PVA formulations yielded conductive cathodes with stable microstructures and uniform particle distribution. Electrochemical characterization exposed that the PVA-based cathode outperformed the PIB-based counterpart, achieving the theoretical capacity of 192 mAh·g⁻¹ even at 1C, whereas the PIB cathode reached a maximum capacity of 145 mAh.g⁻¹ at C/40. Post-mortem analysis confirmed the structural integrity of the cathodes. These findings demonstrate the viability of NMC955 as a high-capacity cathode material compatible with solid-state systems. Full article

Rechargeable aqueous zinc-ion batteries (AZIBs) have garnered significant research attention in the energy storage field owing to their inherent safety, cost-effectiveness, and environmental sustainability. Nevertheless, critical challenges associated with zinc anodes—including dendrite formation, hydrogen evolution corrosion, and mechanical degradation—substantially impede their practical implementation. Grain boundary engineering (GBE) emerges as an innovative solution for zinc anode optimization through the precise regulation of grain boundary density, crystallographic orientation, and chemical states in metallic materials. This study comprehensively investigates the fundamental mechanisms and application prospects of GBE in zinc-based anodes, providing pivotal theoretical insights and technical methodologies for designing highly stable electrode architectures. The findings are expected to promote the development of aqueous zinc batteries toward a high energy density and long cycle life. Full article

This paper investigates the application of non-calcined metal tartrate as a novel alternative pore former to prepare functional ceramic composites to fabricate solid oxide fuel cells (SOFCs). Compared to carbonaceous pore formers, non-calcined pore formers offer high compatibility with various ceramic composites, providing better control over porosity and pore size distribution, which allows for enhanced gas diffusion, reactant transport and gaseous product release within the fuel cells’ functional layers. In this work, nanocrystalline gadolinium-doped ceria (GDC) and Ni-Gd-Ce-tartrate anode powders were prepared using a single-step co-precipitation synthesis method, based on the carboxylate route, utilising ammonium tartrate as a low-cost, environmentally friendly precipitant. The non-calcined Ni-Gd-Ce-tartrate was used to fabricate dense GDC electrolyte pellets (5–20 μm thick) integrated with a thin film of Ni-GDC anode with controlled porosity at 1300 °C. The dilatometry analysis showed the shrinkage anisotropy factor for the anode substrates prepared using 20 wt. The percentages of Ni-Gd-Ce-tartrate were 30 wt.% and 40 wt.%, with values of 0.98 and 1.01, respectively, showing a significant improvement in microstructural properties and pore size compared to those fabricated using a carbonaceous pore former. The results showed that the non-calcined pore formers can also lower the sintering temperature for GDC to below 1300 °C, saving energy and reducing thermal stresses on the materials. They can also help maintain optimal material properties during sintering, minimising the risk of unwanted chemical reactions or contamination. This flexibility enables the versatile designing and manufacturing of ceramic fuel cells with tailored compositions at a lower cost for large-scale applications. Full article

In this work, we have used both plain titania nanotubes, TNTs, and their reduced black analogues, bTNTs, that bear metallic conductivity (prepared by solid state reaction of TNTs with CaH₂ at 500 °C for 2 h), as catalyst supports for the oxygen evolution reaction (OER). Ir was subsequently been deposited on them by the galvanic replacement of electrodeposited Ni by Ir(IV) chloro-complexes; this was followed by Ir electrochemical anodization to IrO₂. By carrying out the preparation of the TNTs in either two or one anodization steps, we were able to produce close-packed or open-structure nanotubes, respectively. In the former case, larger than 100 nm Ir aggregates were finally formed on the top face of the nanotubes (leading to partial or full surface coverage); in the latter case, Ir nanoparticles smaller than 100 nm were obtained, with some of them located inside the pores of the nanotubes, which retained a porous surface structure. The electrocatalytic activity of IrO₂ supported on open-structure bTNTs towards OER is superior to that supported on close-packed bTNTs and TNTs, and its performance is comparable or better than that of similar electrodes reported in the literature (overpotential of η = 240 mV at 10 mA cm⁻²; current density of 70 mA cm⁻² and mass specific current density of 258 mA mg_Ir⁻¹ at η = 300 mV). Furthermore, these electrodes demonstrated good medium-term stability, maintaining stable performance for 72 h at 10 mA cm⁻² in acid. Full article

In a recent investigation the corrosion-fighting potential of five benzaldehyde derivatives were explored: 4-Formylbenzonitrile (BA1), 4-Nitrobenzaldehyde (BA2), 2-Hydroxy-5-methoxy-3-nitrobenzaldehyde (BA3), 3,5-Bis(trifluoromethyl)benzaldehyde (BA4), and 4-Fluorobenzaldehyde (BA5). Benzaldehyde derivative (BA-2) showed a maximum inhibition efficiency of 93.3% at 500 ppm. Several techniques were used to evaluate these compounds’ ability to protect mild steel from corrosion in a 1 M HCl solution, including potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), adsorption isotherms, and computational methods. Supporting techniques Fourier transform infrared spectroscopy (FTIR) and ultraviolet–visible (UV-Vis) spectroscopy were also employed to validate the results. Despite sharing a common benzene ring, the molecules differ in their substituents, allowing for a comprehensive examination of the substituents’ impact on corrosion inhibition. PDP analysis disclosed that the inhibitors exhibited mixed-type inhibition behavior, interacting with anodic as well as cathodic reactions, influencing the corrosion process. EIS analysis revealed that benzaldehyde derivatives formed a protective passive film on the metal, exhibiting high corrosion resistance by shielding the alloy from corrosive attacks. The benzaldehyde inhibitors followed the Langmuir adsorption isotherm, with high R² values near one, indicating a monolayer adsorption mechanism. DFT results indicate that BA 2 is the most effective inhibitor. FTIR and UV-vis spectroscopy revealed the molecular interactions between metal and benzaldehyde derivative molecules, providing insight into the binding mechanism. Experimental results support the outcomes obtained from the molecular dynamic (MD) simulations. Full article

This study focuses on the design and optimization of a monopolar electrode configuration for the hybrid electrochemical treatment of real washing machine wastewater. A combined electrocoagulation (EC) and electro-oxidation (EO) system was optimized to maximize pollutant removal efficiency while minimizing energy consumption. The monopolar setup employed mixed metal oxide (MMO) and aluminum anodes, along with a stainless steel cathode, operating under controlled conditions with sodium chloride as the supporting electrolyte. An applied current density of 15 mA cm⁻² achieved 90% chemical oxygen demand (COD) removal, 98% surfactant degradation, complete turbidity reduction within 120 min, and pH stabilization near 8. Additionally, electrochemical disinfection achieved <2 MPN/100 mL, with no detectable phenols and the presence of organic anions such as oxalate and acetate. These results demonstrate the effectiveness of an optimized monopolar EC–EO system as a cost-efficient and sustainable strategy for wastewater treatment and potential water reuse. Further studies should focus on refining energy consumption and monitoring reaction by-products to enhance large-scale applicability. Full article

In this study, we synthesized anode materials based on iron oxide (Fe₂O₃), titanium dioxide (TiO₂), and reduced graphene oxide (rGO) via the electrophoretic deposition technique. The structural and morphological characteristics of electrodes were examined through various methods including SEM, XRD, Raman, and XPS. Among the investigated compositions, the three-component Fe₂O₃/TiO₂/rGO electrode displayed superior electrochemical characteristics in comparison to the binary Fe₂O₃/rGO and TiO₂/rGO electrodes. Specific capacities of 571, 683, and 729 mAh/g were achieved at 0.5 mA for the respective Fe₂O₃:TiO₂ molar ratios of 1:1, 2:1, and 3:1. The 2:1 ratio configuration offered the most promising balance between cycling stability and capacity, highlighting its potential as a high-performance anode in lithium-ion batteries. This work contributes valuable insights into the synergistic behavior of dual-transition metal oxides in composite electrode design using a low-cost and scalable method. Full article