Abstract
? 2022Metallic 1 T-MoS2 exhibits higher conductivity and electrocatalytic activity for hydrogen evolution reaction (HER) than semiconductor 2 H-MoS2. However, 1 T-MoS2 is a metastable state on thermodynamics, which hinder its further application as catalyst for HER. In this work, we report a new strategy to prepare MoS2 @CoS2/G electrocatalysts (G=graphene) with high-percentage metallic 1 T-MoS2 phase through a simple hydrothermal method followed by sulfurization treatment. We show that the introduction of CoS2 and the sulfurization can both promote the formation of 1 T-MoS2 phase (87.94%) in the MoS2 @CoS2/G electrocatalysts, which leads to improved charge transfer efficiency and electrochemical conductivity, larger surface area, and extensive active sites. These properties ultimately lead to the significantly enhanced catalytic activity of MoS2 @CoS2/G for HER with a small overpotential of 118 mV at 10 mA cm?2, and a small Tafel slope of 53 mV dec?1, as well as excellent durability and cycling stability in acidic electrolyte.
NSTL
Elsevier