WS2 nanosheets as a highly efficient electrocatalyst for hydrogen evolution reaction

Novel nanostructured material WS2 nanosheets (NSs) were prepared through a simple and highly reproducible approach, namely, a mechanical activation strategy by using WO3 and S as the starting materials, and were explored as electrocatalyst for hydrogen evolution reaction (HER). The as-prepared WS2 NSs reveal separate NSs nanostructure with a sheet thickness of less than 10 nm. On the basis of experimental results obtained under various synthesis conditions, a reasonable reaction process and formation mechanism is proposed, in which the pre-treatment of ball milling is assumed to play a key role for the formation of WS2 NSs. Due to its large active sites originating from its unique structural characteristics such as loosely stacked layers, providing highly exposed rims particularly edges, WS2 NSs catalyst has demonstrated high electrocatalytic activity toward HER, which considerably outperforms the commonly used MoS2 (JDC) catalyst.

Unique separate WS2 nanosheets (NSs) were produced through ball-milling S and WO3 followed by an annealing at 600 °C, which exhibit high electrocatalytic activity toward hydrogen evolution reaction due to their highly exposed active sites.Figure optionsDownload as PowerPoint slideHighlights
► We report separate WS2 nanosheets as a highly efficient electrocatalyst for hydrogen evolution reaction.
► WS2 nanosheets were prepared by a mechanical activation strategy, followed by an annealing at an elevated temperature.
► Different annealing temperatures result in various nanostructures.
► Inorganic fullerene nanostructures can also be obtained at a high annealing temperature.
► The pretreatment of ball milling plays a crucial role in the formation of WS2 nanosheets.