Electrochemical imaging uncovers the heterogeneity of HER activity by sulfur vacancies in molybdenum disulfide monolayer  

作　　者：Xiaoli Deng Xiangchao Lu Yang Cao Qianjin Chen 

机构地区：[1]Key Laboratory of Science and Technology of Eco-Textile,Ministry of Education,College of Chemistry and Chemical Engineering,Donghua University,Shanghai 201620,China [2]State Key Laboratory of Physical Chemistry of Solid Surfaces,Collaborative Innovation Center of Chemistry for Energy Materials(iChEM),College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China

出　　处：《Chinese Chemical Letters》2025年第3期212-216,共5页中国化学快报(英文版)

基　　金：the Fundamental Research Funds for the Central Universities(Nos.2232023G-04 and 20720210009);National Natural Science Foundation of China(Nos.NSFC-22274019 and 92163103);National Key R&D Program of China(No.2022YFA1505200)for financial support.Q.Chen is sponsored by National Ten Thousand Talent Program for young top-notch talent。

摘　　要：Engineering of sulfur vacancies on the basal plane of molybdenum disulfide(MoS_(2))may provide effective way to promote the catalytic activity.Although the sulfur vacancy density has previously been correlated with catalytic activity,direct evidence that vacancies create surfaces with enhanced electrocatalytic activity is still lacking.Here,we used a combination of scanning electrochemical cell microscopy(SECCM)with submicrometer resolution and photoluminescence imaging to show that sulfur vacancies in monolayer MoS_(2)microflakes lead to significant spatial heterogeneity in the electrochemical hydrogen evolution reaction(HER)activity.Specifically,colocated multi-microscopy unveils that regions with superior HER activity are associated with sulfur vacancy defects.As the vacancy density increases,the triangular flakes display significantly enhanced and spatially uniformly distributed electrocatalytic activity.Our multi-microscopic imaging approach using SECCM convincingly highlights the spatial heterogeneity of electrocatalytic activity across monolayer MoS_(2)by sulfur vacancy engineering.

关 键 词：Nanoelectrochemistry Scanning electrochemical cell microscopy MoS_(2) monolayers Hydrogen evolution reaction Sulfur vacancy 

分 类 号：O646[理学—物理化学]