Few‐Layered Mo<sub><i>x</i></sub>W<sub>1−<i>x</i></sub>S<sub>2</sub>‐Modified CdS Photocatalyst: One‐Step Synthesis with Bifunctional Precursors and Improved H<sub>2</sub>‐Evolution Activity
Jiangyuan He, Wei Zhong, Ying Xu, Huogen Yu, Jiajie Fan, Jiaguo Yu
Abstract
Introducing W into MoS 2 to fabricate Mo x W 1− x S 2 is a promising strategy to optimize the active‐site density and electrical conductivity of MoS 2 to further improve its H 2 ‐evolution efficiency. However, limited attention has been paid to developing facile and effective methods to prepare a Mo x W 1− x S 2 H 2 ‐evolution cocatalyst, especially the few‐layered Mo x W 1− x S 2 , to boost the photocatalytic H 2 ‐evolution activity of host photocatalyst materials. Herein, a well‐designed Mo x W 1− x S 2 cocatalyst with a few‐layered structure of 5–7 layers and an interlayer spacing of 0.65 nm is in‐situ grown on the CdS surface via a simple one‐step solvothermal method with (NH 4 ) 2 MoS 4 and (NH 4 ) 2 WS 4 as the dual‐functional precursors. In this case, the above dual‐functional precursors can not only transform into the few‐layered Mo x W 1− x S 2 cocatalyst but also provide abundant S 2− ions for the formation of the CdS host photocatalyst. The photocatalytic H 2 ‐evolution results declare that the Mo 0.5 W 0.5 S 2 /CdS photocatalyst acquires the highest H 2 ‐evolution rate of 2968.1 μmol h −1 g −1 , which is higher than that of MoS 2 /CdS by a factor of 3.5. The remarkably promoted H 2 ‐evolution activity of the few‐layered Mo x W 1− x S 2 /CdS is mainly ascribed to the speedy electron transport and efficient H 2 ‐evolution reaction via the Mo x W 1− x S 2 cocatalyst on CdS surface by W‐introduction.