High-yield exfoliation of MoS2 (WS2) monolayers towards efficient photocatalytic hydrogen evolution

Monolayer MoS2 (WS2) nanosheets have triggered tremendous interest due to their fascinating unique properties, but high-yield production of single-layer MoS2 (WS2) still remains an enormous challenge and of great interest. Herein, we report a facile efficient partial etching strategy to tailor thickness and lateral size of MoS2 & nbsp;(WS2) so as to increase the fraction of edges, which remarkably enhanced the yield of monolayer MoS2 (20%) and WS2 (12%) nanosheets by liquid phase exfoliation. As a proof of concept, the exfoliated monolayer MoS2 & nbsp;(WS2) nanosheets were applied as the cocatalysts for photocatalytic hydrogen evolution. Notably, the optimized hybrids exhibit excellent hydrogen evolution performance, which are over 31-fold (MoS2/CdS) and 47-fold (WS2/CdS) higher that of bare CdS counterpart, respectively. Hence, this work not only may pave the new way for the high-yield production of transition-metal dichalcogenides monolayers by liquid phase exfoliation, but also provide the possibility for the further efficiently exfoliating other two-dimension layered materials.