Interface Engineering of Crystalline/Amorphous Co 2 P/CoMoP x Nanostructure as Efficient Electrocatalysts for Hydrogen Evolution Reaction

Exploring highly active and stable non-noble-metal-based electrocatalysts is of great significance for the wide application of hydrogen evolution reaction (HER) in alkaline media. Herein, we report that crystalline/amorphous Co 2 P/CoMoP x nanoparticles containing many active interfaces supported on nickel foam (NF) are highly efficient electrocatalysts for alkaline HER. The interface-engineered crystalline/amorphous Co 2 P/CoMoP x nanostructure is achieved by simple one-step electrodeposition method under a controllable constant current. The optimal electrocatalyst Co 2 P/CoMoP x -0.4/NF in this work exhibits superior activity for the alkaline HER with low overpotentials of −121 mV at −100 mA·cm –2 and prominent electrochemical stability for 50 h. Excellent HER performance can be attributed to a large amount of active interfaces formed between crystalline Co 2 P and amorphous CoMoP x, which provide effective exposure of highly active sites and promote electron transfer. This work may open up a new way for the design and preparation of earth-abundant, low-cost nanostructured materials as high-efficiency HER electrocatalysts for applications in the field of electrocatalysis.