Activation of interfacial P sites of CoP in RuP3/CoP nanosheets boosts hydrogen evolution reaction at all pH values

Abstract Developing cost-effective electrocatalysts with efficient activity and superior stability for hydrogen evolution reaction (HER) over a wide pH range is highly desirable and remains a significant challenge. Herein, we report CoP supported RuP3 nanosheet (RuP3–CoP NS) HER electrocatalysts through an ice-templating method. Constructing heterojunctions of RuP3 and CoP can reduce the loading of scarce Ru species in the catalyst, and meanwhile, maintain efficient HER activity over a wide pH range. The RuP3–CoP NS catalyst with only about 15 wt.% loading of Ru species exhibits remarkable HER performance with excellent catalytic stability and low overpotentials of 25, 60, and 81 mV at 10 mA/cm2 in alkaline, acidic, and neutral media, respectively. The density functional theory calculations indicated that the RuP3 could induce boosting the catalytic activity of P sites in CoP. The enhancement of the HER performance can be attributed to the electron transfer from RuP3 to the P sites in CoP, which changes its electronic structure, and thus, optimizing the adsorption strength of H∗.