High Yield Exfoliation of WS2 Crystals into 1–2 Layer Semiconducting Nanosheets and Efficient Photocatalytic Hydrogen Evolution from WS2/CdS Nanorod Composites

• DOI: 10.1021/acsami.7b15614
• Publication Date: 2018-01-05T16:12:58Z
• Authors: Danyun Xu; Pengtao Xu; Yuanzhi Zhu; Wenchao Peng; Yang Li; Guoliang Zhang; Fengbao Zhang; Thomas E. Mallouk; Xiaobin Fan
• Keywords: Nanorod; Exfoliation joint

Monolayer WS2 has interesting properties as a direct bandgap semiconductor, photocatalyst, and electrocatalyst, but it is still significant challenge to prepare this material in colloidal form by liquid-phase exfoliation (LPE). Here, we report the preparation of 1–2 layer semiconducting nanosheets yield 18–22 wt % modified LPE method that involves preintercalation with substoichometric quantities n-butyllithium. The exfoliated nanosheeets are n-type, have ∼1.78 eV, act cocatalyst CdS nanorods photocatalytic hydrogen evolution using lactate sacrificial electron donor. Up 26-fold increase H2 rate was observed WS2/CdS hybrids compared their pure counterpart, an absorbed photon quantum (AQE) >60% measured optimized photocatalyst.