It is urgent to develop non precious metal electrode materials with significant efficiency and ultrahigh stability to meet the growing demand for renewable energy conversion devices. Herein, heterogeneous nickel-iron sulfide decorated nitrogen-doped-graphene ((Ni,Fe)-Sx-Fe/NGr) with regulated local electronic structure, rich defects, and honeycomb shaped geometric form is synthesized using facile solvothermal and annealing phase transition technology. The obtained target catalyst was characterized for use in a water splitting device, revealing that (Ni,Fe)-Sx-Fe/NGr has lower overpotentials (203 (OER)/166 mV (HER)) for oxygen and hydrogen evolution reaction (OER and HER) compared to NiFeSx (235 (OER)/235 mV (HER)) and NiFe LDH (255 (OER)/308 mV (HER)) at 10 mA/cm2, as well as most reported electrode materials. Meanwhile, (Ni,Fe)-Sx-Fe/NGr demonstrated excellent geometric/chemical stability after 210 h long-term stability testing. Typically, as a dual-functional overall water-splitting electrode, (Ni,Fe)-Sx-Fe/NGr demonstrates lower driving voltage (1.44 V) and considerable stability (110 h) at 10 mA/cm2. Therefore, the developed bimetallic sulfide coupled nitrogen doped graphene with notable activity and stability provides a reference for green and efficient industrial production of green hydrogen.

Heterointerface-mediated magnetic proximity accelerates oxygen evolution.

Controlled construction of hierarchical porous carbon catalysts with Co/CoFe interfaces via Zn sacrifice and Prussian blue analogue growth for oxygen evolution.

The rational design of low-cost bifunctional electrocatalysts for overall water-splitting constitutes a pivotal scientific challenge on the path to carbon-neutral energy cycles. Herein, we report a unique NiPd/Pd heterodimer synthesized via an in situ etching-growth route, which functions as a highly efficient bifunctional catalyst for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). The optimized NiPd/Pd-2 heterodimer delivers exceptional activity, requiring ultralow overpotentials of only 15 mV for HER and 300 mV for OER to achieve a current density of 10 mA cm-2, substantially outperforming the commercial Pt/C (39 mV) and RuO2 (370 mV), respectively. Remarkably, when configured as a symmetric NiPd/Pd-2||NiPd/Pd-2 electrolyzer, it requires a cell voltage of merely 1.36 V to drive overall water splitting at 10 mA cm-2, surpassing the performance of the Pt/C||RuO2 couple (1.70 V). Structural and chemical characterizations after prolonged HER/OER reveal the preserved heterodimeric architecture of NiPd/Pd, with the increased content of Ni-O-O-Pd motif imparting enhanced stability in acidic conditions. Consequently, the NiPd/Pd heterodimer can maintain stable operation of HER, OER, and overall water electrolysis for 24 h without significant attenuation. Furthermore, the electrolyzer can be efficiently powered by simulated renewable sources, highlighting its great potential for sustainable energy-conversion devices.

Boosting the photoelectrochemical performance of BiVO4 via element dopant engineering: concurrent optimization of band structure and oxygen vacancy.

Precisely modulating the coordination structure of neighboring metal atomic sites is urgently required yet remains technically challenging. Herein, we report a carbon-vacancy-induced Fe coordination environment modulation in FeZn dual-atom sites (FeZnN6-VC) to boost bifunctional oxygen electrocatalysis. Finite element simulation and electronic structure characterization reveal that carbon vacancies promote electron transfer from Fe-N4 to neighboring Zn-N4 sites, establishing favorable electronic interactions. In situ Raman spectroscopy further identifies the key O-O- intermediate (corresponding to OOH*) and the FeOOH active phase during oxygen evolution reaction (OER), both showing significantly lowered onset potentials. Compared with conventional FeZn dual-atom catalysts, FeZnN6-VC achieves a 174 mV decrease in OER overpotential at 10 mA cm-2 and exhibits improved oxygen reduction reaction performance in alkaline media. The corresponding quasi-solid-state Zn-air battery delivers a long cycling life of 82.3 h at 50 mA cm-2. This work offers a versatile carbon-vacancy strategy to tune the local coordination of dual-atomic sites for advanced electrocatalysis.

Enhanced dual-mechanism oxygen evolution through partial anion filling of oxygen vacancies in spinel oxides.

Synergistic Zn and CoS2 modulation of the d-band center of Fe-NC sites for bifunctional oxygen electrocatalysis in Li-O2 batteries.

Intrabubble coupled evolution of microdroplets and nanobubbles in oxygen evolution reaction

Fe-doping engineering of hierarchical NiS/Co2.67S4 nanoarrays as bifunctional electrocatalysts toward high-efficiency overall water splitting.

Low-cost transition metal high-entropy nanoalloys are emerging as sustainable alternatives to platinum group electrocatalysts. Synthesis conditions of single-phase solid solutions can alter phase stability, causing surface composition changes that affect electrocatalytic performance. Here, we propose to exploit the metastability of carbon-doped Cantor alloy-based amorphous high-entropy alloy nanoparticles produced by nanosecond-pulsed laser synthesis in organic solvents. In situ electron microscopy reveals crystallization and partitioning of elements upon heating to 600 °C, forming heterostructured nanoparticles with reinforced carbon shells that exhibit a 5- to 7-fold enhancement of the electrocatalytic activity compared to the as-synthesized counterparts for the oxygen evolution reaction. Discernible differences in elemental dissolution profiles under reaction conditions indicate the changes in the surface atom arrangements that influence the electrocatalytic behavior. We demonstrate the strategic utilization of phase metastability in high-entropy nanoalloys through post-synthesis annealing to enhance the electrochemical activity of laser-generated nanoparticles.

Synergistic interfacial coordination and Iron-cobalt orbital coupling for high-performance photoelectrochemical water oxidation.

Amorphous IrOx buffer layer stabilizes low-valence Ir centers and reinforces IrO hybridization in hierarchical multilayered Ir-IrCoOx for acidic oxygen evolution.

Upcycling PET waste into CoNi-based electrocatalysts for ethylene glycol oxidation integrated with energy-efficient H2 evolution.

Bimetallic two-dimensional π-d conjugated benzenehexathiol (BHT) frameworks are emerging as a versatile platform for oxygen evolution reaction (OER) electrocatalysis, yet the vast compositional space and the known limitations of computational hydrogen electrode (CHE)-based free-energy rankings make purely thermodynamic screening unreliable. Building on our previous combined experimental-computational study of NiFe-BHT, we here use the local magnetic moment of the transition-metal node and the *OH adsorption energy (Ead) as physically motivated, intrinsic activity indicators to evaluate a series of monometallic TM-BHT (TM = Cu, Zn, Cd, Pd, Ni, Co, Fe, Mn) and Mn-based bimetallic MnTM-BHT (TM = Fe, Co, Ni, Cu) frameworks at two stoichiometries (MnTM5 : 1 and MnTM1 : 5). Density functional theory (DFT) calculations reveal an apparent trend between the TM local magnetic moment and Ead(*OH), with high-spin Mn-BHT exhibiting nearly neutral binding (Ead = -0.015 eV). Among the bimetallic compositions examined, MnFe5 : 1-BHT uniquely shifts Ead(*OH) on the Mn site into the moderately negative regime (-0.647 eV) while preserving the high local Mn spin moment (2.757 µB). CHE-level Gibbs free-energy profiles, used here only as an internal mechanistic consistency check, suggest a dual-site picture in which Fe acts as the kinetic hotspot and electronically tunes the neighboring Mn centers. Convex-hull and Boltzmann-transport calculations further indicate that MnFe5 : 1-BHT is metastable to an extent comparable with already-synthesized monometallic BHTs and retains adequate intrinsic conductivity. The convergence of four independent criteria, moderated *OH binding on Mn, preserved Mn high-spin character, accessible metastability, and adequate conductivity, rather than any single ΔG value, supports MnFe5 : 1-BHT as a concrete target for experimental realization.

Coupling of CO2 electroreduction and biomass electrooxidation: challenges, design principles, and perspectives.

Binder-free Ti3C2Tx MXene-assisted CoFe-LDH as highly stable bifunctional electrocatalyst for both oxygen and hydrogen evolution reactions under high current density

Recent advances in engineering oxyhydroxides for boosting electrocatalytic oxygen evolution reaction

Enhanced oxygen evolution reaction in alkaline media using cobalt‑manganese oxide and reduced graphene oxide anchored with W, Ni, and Mn single metal atom oxides

Synthesis and morphology of Ba(OH)2 flakes governing phase-dependent electrochemical performance