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

Design and fabrication of a highly active and earth-abundant hydrogen evolution reaction (HER) electrocatalyst which can work in a wide range of pHs are pivotal for sustainable hydrogen production. In this work, we developed a novel CoP3/CoMoP heterogeneous nanosheet array supported on nickel foam (CoP3/CoMoP/NF HNAs) synthesized from a one-pot phosphidation of CoMoO4 nanosheet arrays. Within this heterojunction, plenty of tiny CoP3 nanoparticles were embedded in the CoMoP nanosheet, forming abundant heterostructure interfaces, which can provide more active sites and improve the electric conduction, consequently improving the catalytic efficiency. The resulting CoP3/CoMoP/NF HNAs exhibited excellent HER activities with a low overpotential of 125 mV at 10 mA cm(-2) and good durability in the acidic media, which ranks in the most-efficient Co-based TMPs electrocatalysts. Furthermore, the CoP3/CoMoP/NF HNAs showed high electrocatalytic HER activities and durability in both neutral and alkaline media. This facile synthesis of a CoP3/CoMoP/NF heterostructure provides a novel way for the fabrication of other heterojunction metal phosphides for hydrogen production from water splitting.