Li‐Ion Intercalated Exfoliated WS₂ Nanosheets with Enhanced Electrocatalytic Hydrogen Evolution Performance

Abstract

Abstract Tungsten disulfide (WS 2 ) as a 2D layered material shows good application in the field of electrocatalysis due to its unique 2D structure, excellent electronic properties, and catalytic activity. However, the electrocatalytic performance of bulk WS 2 materials is limited due to the lack of active sites. Hence, a few layers of WS 2 nanosheets are prepared by a simple method of lithium (Li)‐ion intercalation exfoliation, and enhanced electrocatalytic hydrogen evolution performance is demonstrated compared to bulk WS 2 . This method can not only realize the large‐scale preparation of WS 2 nanosheets, but also the obtained WS 2 nanosheets have a larger lateral size, a good lattice structure, and no chemical impurities remain. Most importantly, it is realized that the reduction in the thickness of WS 2 nanosheets will generate additional active sites from the ultrathin planar structure, thereby improving electrocatalytic activity. The exfoliated WS 2 nanosheets show a smaller overpotential compared to the bulk WS 2 , the overpotential is about 320 mV at 10 mA cm –2 . This work shows that Li‐ion intercalation exfoliated method is an efficient strategy to prepare 2D nanosheets materials and effectively improve its electrocatalytic performance.