FeP/Ni2P nanosheet arrays as high-efficiency hydrogen evolution electrocatalysts

Transition metal phosphides (TMPs) are attracting extensive attention as alternatives to noble metal-based electrocatalysts for hydrogen evolution reaction (HER). However, it is desirable and a long-term challenge to design and fabricate TMPs electrocatalysts for HER with high efficiency and durability. Herein, iron phosphide (FeP)/nickel phosphide (Ni2P) nanosheet arrays supported on carbon paper (FeP/Ni2P/CP) as a highly efficient electrocatalyst for hydrogen evolution is reported. The self-supported FeP/Ni2P/CP catalyst exhibits superior hydrogen evolution reaction (HER) catalytic activity with low overpotentials of 51 mV and 122 mV in 0.5 M H2SO4, 46 mV and 98 mV in 1 M KOH to drive the current density of 10 and 100 mA cm(-2), respectively. Meanwhile, FeP/Ni2P/CP exhibits good durability with negligible attenuation of current density for 50 h in both acidic and alkaline solutions. The combined experimental and theoretical study demonstrates the synergistic effect and modulation of electronic structure between FeP and Ni2P, which endows FeP/Ni2P with improved intrinsic activity. In addition, the increased accessible active sites and faster charge transfer rate collectively contribute to the enhanced prominent HER performance.

Automated summary

This study reports a highly efficient hydrogen evolution electrocatalyst FeP/Ni2P/CP, which exhibits superior catalytic activity and good durability in both acidic and alkaline solutions. The improvement in catalytic performance is achieved through the synergistic effect and modulation of electronic structure between FeP and Ni2P, as well as the increased accessible active sites and faster charge transfer rate.