Fe-Doped CoP holey nanosheets as bifunctional electrocatalysts for efficient hydrogen and oxygen evolution reactions

Two-dimensional porous nanosheet material has attracted great attention as a promising electrocatalyst for water splitting. Herein, mesh-like Fe-doped CoP holey nanosheets (Fe–CoP HNSs) is synthesized by a facile phosphorization treatment. The Fe–CoP HNSs catalyst features abundant active sites, short charge and ion transport pathways, and favorable mass transfer kinetics, which are conductive to promote the water splitting reaction. Remarkably, the Fe–CoP HNSs catalyst exhibits superior catalytic activity towards hydrogen and oxygen evolution reaction with low overpotentials of 79 and 220 mV to reach 10 mA cm−2, respectively. Furthermore, the assembled Fe–CoP HNSs||Fe–CoP HNSs electrolyzer needs a low cell voltage of 1.60 V to deliver 20 mA cm−2, which is higher than many reported transition metal phosphides electrocatalysts. This work sheds light on the fabrication of transition-metal compound electrocatalyst with holey nanosheet structure by element doping for renewable energy production.