CoP₃/CoMoP Heterogeneous Nanosheet Arrays\nas Robust Electrocatalyst for pH-Universal Hydrogen Evolution Reaction

Abstract

Design\nand fabrication of a highly active and earth-abundant hydrogen\nevolution reaction (HER) electrocatalyst which can work in a wide\nrange of pHs are pivotal for sustainable hydrogen production. In this\nwork, we developed a novel CoP₃/CoMoP heterogeneous nanosheet\narray supported on nickel foam (CoP₃/CoMoP/NF HNAs) synthesized\nfrom a one-pot phosphidation of CoMoO₄ nanosheet arrays.\nWithin this heterojunction, plenty of tiny CoP₃ nanoparticles\nwere embedded in the CoMoP nanosheet, forming abundant heterostructure\ninterfaces, which can provide more active sites and improve the electric\nconduction, consequently improving the catalytic efficiency. The resulting\nCoP₃/CoMoP/NF HNAs exhibited excellent HER activities with\na low overpotential of 125 mV at 10 mA cm^–2 and\ngood durability in the acidic media, which ranks in the most-efficient\nCo-based TMPs electrocatalysts. Furthermore, the CoP₃/CoMoP/NF\nHNAs showed high electrocatalytic HER activities and durability in\nboth neutral and alkaline media. This facile synthesis of a CoP₃/CoMoP/NF heterostructure provides a novel way for the fabrication\nof other heterojunction metal phosphides for hydrogen production from\nwater splitting.