Activating inert basal planes of MoS2 for hydrogen evolution reaction through the formation of different intrinsic defects
作者单位：Department of PhysicsSoutheast University
会议名称：《中国化学会第30届学术年会-第四十分会：纳米体系理论与模拟》
会议日期：2016年
学科分类：081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术]
关 键 词：Molybdenum Disulphide Hydrogen Evolution Reaction Defect and Density Functional Theory
摘 要：Nanoscale molybdenum disulphide(MoS) has attracted ever-growing interest as one of the most promising non-precious catalysts for hydrogen evolution reaction(HER). However, the active sites of pristine MoS are located at the edges, leaving large area of basal planes useless. Here, we systematically evaluate the capabilities of 16 kinds of structural defects including point defects(PDs) and grain boundaries(GBs) to activate the basal plane of MoS monolayer. Our first-principle calculations show that six types of defects(i.e., V, V, Mo PDs, 4|8a, S bridge and Mo-Mo bond GBs) can greatly improve the HER performance of the in-plane domains of MoS. More importantly, Vs and Mo PDs, S bridge and 4|8a GBs exhibit outstanding activity in both Heyrovsky and Tafel reactions as well. Moreover, the different HER activities of defects are well understood by an amendatory band-center model, which is applicable to a broad class of systems with localized defect states. Our study provides a comprehensive picture on the defect-engineered HER activities of MoS monolayer and opens a new window for optimizing the HER activity of two-dimensional dichalcogenides for future hydrogen utilization.