Excellent catalytic performance of (FC)P-(NFC)S/NF catalyst for oxygen evolution reaction at high current density

Water electrolysis to produce high-purity hydrogen has been regarded as the most promising and attractive method for renewable energy production. The intrinsic high kinetic barrier of the involved electrode reactions, especially that of the anodic oxygen evolution reaction (OER), however severely hinders the application of the water electrolysis technology for large scale hydrogen production. In this paper, a nano-composite Fe- and Co-based material containing crystalline metal sulfide ((NiFeCo)S) and amorphous metal phosphide ((FeCo)P) was in-situ grown on the surface of foam nickel (NF). The (FC)P-(NFC)S/NF catalyst exhibits ultra-high activities for OER at high current densities in 1.0 M KOH, delivering 500 and 1000 mA cm −2 at ultralow overpotentials of 274 and 280 mV, respectively with a small Tafel slope of 37.8 mV dec −1 . The excellent catalytic activities of (FC)P-(NFC)S/NF far exceed those of the reference single-component (FC)P/NF and (NFC)S/NF catalysts, and also exceed those of most non-noble metal catalysts reported in literature. Besides, the (FC)P-(NFC)S/NF catalyst exhibits high stability with almost no significant activity attenuation after the chronopotentiometric test at both 100 and 500 mA cm −2 for 40 h. The synergistic effects between the metal sulfide and metal phosphide have positive impacts on the OER activity through increasing the surface area, enhancing the reactivity of each active site, improving the electrical conductivity as well as the interface between the crystalline and amorphous phases. The present work provides a new strategy to develop cost-effective and efficient electrocatalysts toward OER and water electrolysis.