MoS₂ nanosheets: A designed structure with high active site density for the hydrogen evolution reaction

Two-dimensional MoS₂ nanosheets (NSs) with high active site density were designed for the hydrogen evolution reaction (HER) through a microdomain reaction method. The effect of the annealing temperature on the microstructure and the HER performance of MoS₂ NSs was examined, and a plausible relation between the stack structures of the MoS₂ catalysts and their HER performance was also explored. The MoS₂ NS electrocatalyst obtained at 550 C reveals the best HER performance with a relatively small Tafel slope of 68 mV/dec. Both the exposed surface area and active site density are very important for providing a large amount of active sites. The present work has been proved to be an efficient route to achieve a high active site density and a relatively large surface area, which might have potential use in photoelectrocatalytic water splitting.