Tuning the Intrinsic Activity and Electrochemical Surface Area of MoS2 via Tiny Zn Doping: Toward an Efficient Hydrogen Evolution Reaction (HER) Catalyst

Abstract Molybdenum sulfide (MoS 2 ) is considered as an alternative material for commercial platinum catalysts for electrocatalytic hydrogen evolution reaction (HER). Improving the apparent HER activity of MoS 2 to a level comparable to that of Pt is an essential premise for the commercial use of MoS 2 . In this work, a Zn‐doping strategy is proposed to enhance the HER performance of MoS 2 . It is shown that tiny Zn doping into MoS 2 leads to the enhancement of the electrochemical surface area, increases in proportion of HER active 1T phase in the material and formation of catalytic sites of higher intrinsic activity. These benefits result in a high‐performance HER electrocatalyst with a low overpotential of 190 mV(@10 mA cm −2 ) and a low Tafel slope of 58 mV dec −1 . The origin for the excellent electrochemical performance of the doped MoS 2 is rationalized with both experimental and theoretical investigations.