PNNL

Abstract

In this study, we report a non-precious metal catalyst for high-efficiency hydrogen evolution reaction (HER). A self-organized S-doped MoP nanoporous layer (S-MoP NPL) is achieved through a facile electrochemical anodic treatment and a two-step chemical vapor deposition process, which can be directly used as a binder-free catalyst for HER in pH-universal electrolytes. S-MoP NPL exhibits excellent HER activity with a low overpotential of 86 mV at 10 mA cm-1 and low Tafel slope of 34 mV dec-1 in 0.5 M H2SO4 electrolyte. Moreover, S-MoP NPL also shows high HER performance in basic and neutral electrolytes. First principle based density functional theory (DFT) calculations were performed to support our experiment. The present DFT calculations show that the H2 formation (via Volmer-Heyrovsky mechanism) from the reaction of a metal (Mo) absorbed hydride with a solvated proton is favored over S-MoP than MoS2. Both experimental and computational studies demonstrate that the extraordinary HER activity and stability performance displayed by a MoP catalyst can be enhanced by S-doping, opening up a promising paradigm for the rational design of high-performance non-precious metal catalyst for hydrogen generation.