Tetrahedral Zn2+ doping LiNi0.6Mn0.2Co0.2O2 improves discharge capacity retention by altering surface Ni valence during cycling and preventing oxygen evolution

Designing robust and earth-abundant oxygen evolution reaction (OER) catalysts for alkaline water electrolysis requires precise control of crystal phase, surface chemistry, and electronic structure. Here, we report a simple hydrothermal strategy to tune Co-Fe catalysts through phosphate-mediated phase engineering, evolving from layered double hydroxides (low P) to potassium cobalt phosphate frameworks (intermediate P) and hydrated cobalt phosphates (high P). Structural evolution reveals the role of alkali cations in stabilizing phosphate phases under alkaline conditions. Electrochemical evaluation in 1M KOH shows that phosphate incorporation significantly enhances OER activity, with intermediate P contents achieving the best balance of low overpotential (257-265 mV at 10 mA cm −2 ), small Tafel slopes (42-47 mV dec −1 ), and improved durability. Fe-containing catalysts outperform the Co-only analogue, demonstrating that phosphate incorporation must be coupled with Fe to enable efficient charge transfer and mixed-valence redox. Post-stability analysis indicates that the phosphate frameworks act as structure-directing precatalysts that reconstruct into the active oxyhydroxide phase during OER. These trends are validated in a single-cell anion exchange membrane water electrolyzer, where phosphate-containing CoFe anodes achieve lower cell voltages. Overall, this work establishes phosphate-Fe synergy and scalable hydrothermal synthesis as key design strategy for high-performance Co-based OER catalysts. • Hydrothermal synthesis tunes CoFe catalysts via phosphate phase control. • Fe incorporation modulates electronic structure of phosphate frameworks. • Optimized catalysts deliver ∼260 mV at 10 mA cm −2 for alkaline OER. • Phosphate phases reconstruct into active CoFe oxyhydroxides. • Performance validated in single-cell AEM water electrolysis.

Screening of transition metal-doped TaS2 as a highly efficient bifunctional electrocatalyst for oxygen reduction and evolution reactions

Interactive effect of melatonin and gamma aminobutyric acid in Nostoc muscorum and Anabaena sp. and their mechanisms of cadmium toxicity alleviation

Ni-site local magnetism regulated via intrinsic exchange in NiFeCo electrocatalysts.

• Filtration maximizes •OH production by activating the full electrode area. • Flow-through behavior shifts the oxygen evolution potential anodically. • Flow-through mode is the optimal operation condition for EF. • Flow-by mode loses over 70% of the active area at high flow rates. Electrofiltration is an emerging electrochemical technique that enables simultaneous filtration and advanced oxidation for water treatment, offering improved control over mass transport and surface activation compared with conventional electrochemical process. Ceramic 3D Sb-doped SnO 2 porous electrodes have been proven to be suitable electrofiltration anodes. In this work, the impact of hydrodynamics on the electrochemical behavior and oxidizing capability of such electrofiltration anodes was investigated. Cyclic voltammetry revealed that, without filtration, the system behaves as a quasi-2D flow-by electrode with low internal resistance, limited electroactive area and low oxygen evolution potential at high injection flow. Under filtration, the system behaves as a 3D flow-through electrode exhibits a higher ohmic resistance for all the tested flow rates, an anodic shift of the oxygen evolution potential and a higher activated area. The ability to generate hydroxyl radicals was assessed by salicylic acid electrofiltration and quantification of 2,5- dihydroxybenzoic acid and 2,3-dihydroxybenzoic acid, confirming that hydroxyl radical production at 20 L/h is effective both, without filtration and with filtration; whereas at 60 L/h it is strongly hindered in flow-by mode and only partially recovered under flow-through operation. These findings highlight the critical role of hydrodynamics in electrofiltration with porous ceramic Sb–SnO₂ anodes and provide a mechanistic link between flow regime, electrochemical response and radical-mediated oxidation performance.

A bioelectrocatalytic glucose oxidation cascade for energy-efficient electrocatalysis applications.

The development of efficient and durable electrocatalysts for the oxygen evolution reaction (OER) is essential for advancing large-scale water electrolysis, particularly in acidic media and real seawater. In this work, Ti/(RuO 2 ) x (Mn 3 O 4 ) 1- x materials with distinct amounts of Ru and Mn were synthesized via the Pechini method and subjected to three distinct heating treatments named conventional furnace, hybrid microwave, and CO₂ laser, aiming to evaluate the influence of thermal processing on their structural and electrocatalytic properties. Regardless of the heating method, it was possible to assign diffraction peaks for RuO 2 and Mn 3 O 4 phases. However, scanning electron microscopy revealed that faster heating approaches produced more compact and homogeneous surfaces, reducing crack formation compared to conventional heating. The heating method strongly impacts electrochemical activity, in which thermal treatment in both microwave and CO 2 laser produces more active materials (lower overpotential and lower Tafel slopes) for OER compared to a conventional furnace. Microwave-treated materials presented the highest electrochemically active surface area, whereas laser-treated anodes exhibited the lowest charge transfer resistance as evaluated by electrochemical impedance spectroscopy, resulting in superior intrinsic activity. Moreover, long-term electrolysis tests in both acidic real seawater electrolytes demonstrated stable performance of Ti/(RuO 2 ) 0.5 (Mn 3 O 4 ) 0.5 electrode prepared in the microwave. After 90 h at 10 mA cm −2 in acidic media, both XPS and SEM/EDS analyses revealed morphological changes with Mn lixiviation. Overall, the results highlight that rapid and energy-efficient heating methods are highly effective for tailoring RuO 2 -Mn 3 O 4 mixed oxides, offering a promising route to produce low-cost, stable, and high-performance anodes for sustainable hydrogen generation.

Ta-doped cerium oxide electrocatalysts for enhanced oxygen evolution in anion exchange membrane water electrolysis

Proton exchange membrane water electrolyzers (PEMWEs) play a key role in green hydrogen production, but their large-scale adoption has been hampered by the high cost of iridium-based anodes. In this study, we report a wet-chemical synthesis of bimetallic IrPt nanoparticles using ethanol (IrPt-Et) and isopropanol (IrPt-IPA) as solvents, which reduced the Ir content by 50% while maintaining high oxygen evolution reaction (OER) activity. Comprehensive characterization of the samples revealed that IrPt-Et forms ultra-small nanoparticles (NPs) of about 2–3 nm with the presence of IrO x surface phases, while IrPt-IPA contains larger agglomerates of 2.5–4.8 nm with a less uniform distribution of Ir and Pt. Electrochemical testing in 0.1 M HClO 4 shows that IrPt-Et delivers a current density of 10.6 mA/cm 2 at 1.53 V, which is twice the activity of commercial Ir-black. The mass activity reaches 697 mA/mg Ir – 4 times higher than Ir-black - due to the optimal utilization of Ir. In contrast, the heterogeneous composition of IrPt-IPA and large NPs lead to worse performance in OER. XPS analysis of post-activation samples confirmed that both catalysts undergo surface oxidation under OER conditions, but the pre-oxidized surface of IrPt-Et facilitates the formation of a more active and stable interface. This study demonstrates that solvent choice in synthesis influences a combination of factors – including reduction kinetics, particle size, alloy homogeneity, and surface oxidation – to yield highly active bimetallic catalysts with reduced iridium content, which is critical for the larger-scale implementation of PEMWE technologies. • Facile wet-chemical synthesis allows to obtain highly active IrPt alloy nanoparticles • Solvent choice (ethanol vs. isopropanol) controls microstructure and composition • Ethanol enables ultra-small (2-3 nm) bimetallic IrPt nanoparticles • Optimized IrPt catalysts show high oxygen evolution reaction activity and stability

Intermediate-mediated *OH migration activates lattice oxygen in Co-CoO Schottky heterostructures for efficient oxygen evolution

Engineering a self-sufficient ECL system: Oxygen-vacancy-driven O2 generation and nanozyme confinement for bioanalysis.

Carbon black as a conductive modifier boosts the oxygen evolution reaction of FeCoNi high-entropy oxides: Experiment and density functional theory methods

Exploring the composition space of quinary metal oxides for oxygen evolution reaction on an automated platform

Defect engineering in layered double hydroxides via surface reconstruction for enhanced oxygen evolution reaction and electrochemical dye degradation

An agglomerate electrochemical model for oxygen evolution reaction kinetics and mass transport in proton exchange membrane water electrolysis

Amorphous/crystalline heterophase induced S2− migration and oxidation for enhanced oxygen evolution reaction

MXenes for hydrogen evolution and oxygen evolution reactions: Synthesis, properties, and mechanistic insights

Concentration-dependent effects of Zr4+ ions on anodic oxygen evolution and cathodic copper deposition during copper electrowinning

Structural amorphization triggers direct O-O coupling for efficient and durable acidic oxygen evolution reaction