VS <sub>2</sub> Microflowers with In Situ Embedded Few-Layer MoS <sub>2</sub> Nanobelts for Enhanced Hydrogen Evolution Reaction at High Current Density
Rui Xu, Jianfeng Huang, Liyun Cao, Feng Li, Yongqiang Feng, Lingjiang Kou, Qianqian Liu, Dan Yang, Liangliang Feng
Abstract
Metallic VS 2 has emerged as a highly promising nonprecious electrocatalyst for hydrogen evolution reaction (HER) due to its desirable electronic conductivity and potential catalytic active sites located at the layer edge and the basal plane. The full exposure and enhancement of catalytic active sites toward VS 2 materials is very crucial for promoting their HER activity. Herein, we report the synthesis of a novel self-assembled VS 2 microflower with in situ embedded few-layer MoS 2 nanobelts grown on Mo foil (VS 2 /MoS 2 /MF) by a facile one-pot hydrothermal method. Benefitting from abundant exposed edge active sites and fast electron and mass transport as well as strong electronic interactions between VS 2 and MoS 2 , the as-obtained VS 2 /MoS 2 /MF heterostructure exhibits remarkable electrocatalytic performance for HER at large current densities in 0.5 M H 2 SO 4 solution, with small overpotentials of 282 and 336 mV at 500 and 1000 mA cm −2 respectively, much lower than those of 20% Pt/C/MF, a small Tafel slope of 51 mV dec −1 and a durable long-term stability for at least 24 h. The well-intergrated VS 2 /MoS 2 /MF electrode has the promise for industrial large-scale prodution of hydrogen.