Catalysis Communications (Apr 2022)
Activating MoS2 via electronic structure modulation and phase engineering for hydrogen evolution reaction
Abstract
The local electronic configuration of active sites in molybdenum disulfide (MoS2) could significantly alter the intrinsic activity towards hydrogen evolution reaction (HER). Herein, we report that the HER performance of MoS2 electrocatalysts was boosted via bismuth and palladium co-doping. The introduction of heteroatom Bi successfully altered the local electronic configuration of S atoms in the MoS2 inert basal plane to form an electron-enriched environment, conducive to boost active site density and proton adsorption, as experimentally verified by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). Furthermore, after activating the MoS2 via Pd doping, a phase transition to stable 1 T phase occurred which was verified by Raman. In acidic media, the as-prepared Bi/Pd-MoS2 catalyst exhibited excellent electrochemical HER performance in terms of a low overpotential of -114 mV at a current density of 10 mA cm−2, a small Tafel slope of 65 mV dec−1, and outstanding long-term stability.