Enhanced Hydrogen Evolution Reaction Performance in Alkaline Water Electrolysis: Tuning the 1T Structure of Ni Doped MoS2 Via Co-Sputtering System

Abstract

Molybdenum disulfide (MoS2) is a promising catalyst for the hydrogen evolution reaction (HER) in alkaline media due to its low cost and abundance. However, its HER activity is not sufficient for practical application because of its electrochemically inert basal plane and suboptimal hydrogen adsorption energy for HER. Herein, we present a facile synthesis approach to fabricate MoS2/Ni HER electrode with 1T structure using co-sputtering of both MoS2 and Ni. Our results indicated that Ni doping plays a critical role in introducing 1T phase in MoS2 structure, leading to an active basal plan, optimized hydrogen adsorption energy, and strong adhesion between the catalyst film and Ni substrate for highly efficient HER performance and durability. We confirmed that the 1T-phase yield, morphologies, and HER activity are affected by sputtering parameters. Our optimized MoS2/Ni electrode exhibited an overpotential of ~91 mV at 10 mAcm-2 and no significant change in HER performance after 1000 cycles operation in 1 m KOH. Single cell test including our optimized electrode exhibited enhanced overpotential and durability compared to a reference cell, highlighting the potential for commercialization in alkaline water electrolysis industry.