Kinetic Study of Hydrogen Evolution Reaction over Strained MoS2 with Sulfur Vacancies Using Scanning Electrochemical Microscopy
By Li, Hong; Du, Minshu; Mleczko, Michal J.; Koh, Ai Leen; Nishi, Yoshio; Pop, Eric; Bard, Allen J.; Zheng, Xiaolin
Published in Journal of the American Chemical Society
2016
Abstract
Molybdenum disulfide (MoS2), with its active edge sites, is a proposed alternative to platinum for catalyzing the hydrogen evolution reaction (HER). Recently, the inert basal plane of MoS2 was successfully activated and optimized with excellent intrinsic HER activity by creating and further straining sulfur (S) vacancies. Nevertheless, little is known about the HER kinetics of those S vacancies and the additional effects from elastic tensile strain. Herein, scanning electrochemical microscopy was used to determine the HER kinetic data for both unstrained S vacancies (formal potential Ev0 = ?0.53 VAg/AgCl, electron-transfer coefficient ?v = 0.4, electron-transfer rate constant kv0 = 2.3