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Developing efficient and durable oxygen evolution reaction (OER) electrocatalysts with non-noble elements is particularly urgent for electrochemical water splitting. Herein, we report heterostructural Ni3S2–Fe5Ni4S8 hybrids directly grown on redox-NiFe foams (denoted as NFS/rNF) as excellent pre-catalysts for OER in 1 M KOH media. The electrochemical performance can be tuned by amount of sulfur source, and the optimized electrode only needs low overpotentials of 199 mV and 240 mV to attain 10 mA cm−2 and 100 mA cm−2, respectively. Moreover, the overpotential is further reduced to 231 mV to deliver 100 mA cm−2 after multi-cyclic voltammogram scans, due to the exposure of abundant in situ generated Ni(Fe)OOH species. Excellent stability with continuous 40 h operation is also demonstrated. Our study provides a new strategy for direct synthesis of self-standing integrated hybrid electrodes for efficient and durable water oxidation. [ABSTRACT FROM AUTHOR]

Herein, a series of phosphorus-doped CoMoO4 rod bundles electrocatalysts on 3D nickel foams have been successfully synthesized and exploited as efficient hydrogen evolution reaction (HER) electrocatalyst in 1 M KOH. The incorporation of phosphorus into CoMoO4 can significantly promote the HER activity, and the CoMoO4 bundles phosphorized at 350 °C exhibited the optimum activity, which only required low overpotentials of 56 and 148 mV to deliver cathodic current densities of 10 mA cm−2 and 100 mA cm−2, respectively. This electrode also presented considerable long-term electrochemical stability with negligible delay after 30 h operation and 3000 accelerated cyclic voltammetry cycles. Our study provides a superior earth-abundant catalyst for efficient HER in alkaline media, which also suggests that P doping engineering is an effective way to boost the HER activity of transition metal-based oxides. [ABSTRACT FROM AUTHOR]