Zhang Jian, Li Jiandong, Huang Huajie, Chen Wei, Cui Yan, Li Yonghua, Mao Weiwei, Zhu Xinbao, Li Xing'ao
New Energy Technology Engineering Lab of Jiangsu Province, College of Science, Nanjing University of Posts & Telecommunications (NUPT), Nanjing, 210023, China.
State Key Laboratory of Organic Electronics and Information Displays and Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications (NUPT), Nanjing, Jiangsu, 210023, P. R. China.
Small. 2022 Nov;18(47):e2204557. doi: 10.1002/smll.202204557. Epub 2022 Oct 10.
Defect engineering of transition metal dichalcogenides (TMDCs) is important for improving electrocatalytic hydrogen evolution reaction (HER) performance. Herein, a facile and scalable atomic-level di-defect strategy over thermodynamically stable VSe nanoflakes, yielding attractive improvements in the electrocatalytic HER performance over a wide electrolyte pH range is reported. The di-defect configuration with controllable spatial relation between single-atom (SA) V defects and single Se vacancy defects effectively triggers the electrocatalytic HER activity of the inert VSe basal plane. When employed as a cathode, this di-defects decorated VSe electrocatalyst requires overpotentials of 67.2, 72.3, and 122.3 mV to reach a HER current density of 10 mA cm under acidic, alkaline, and neutral conditions, respectively, which are superior to most previously reported non-noble metal HER electrocatalysts. Theoretical calculations reveal that the reactive microenvironment consists of two adjacent SA Mo atoms with two surrounding symmetric Se vacancies, yielding optimal water dissociation and hydrogen desorption kinetics. This study provides a scalable strategy for improving the electrocatalytic activity of other TMDCs with inert atoms in the basal plane.
过渡金属二硫属化物（TMDCs）的缺陷工程对于提高电催化析氢反应（HER）性能至关重要。在此，报道了一种在热力学稳定的VSe纳米片上简便且可扩展的原子级双缺陷策略，该策略在宽电解质pH范围内对电催化HER性能产生了有吸引力的改善。单原子（SA）V缺陷与单Se空位缺陷之间具有可控空间关系的双缺陷构型有效地触发了惰性VSe基面的电催化HER活性。当用作阴极时，这种双缺陷修饰的VSe电催化剂在酸性、碱性和中性条件下分别需要67.2、72.3和122.3 mV的过电位才能达到10 mA cm的HER电流密度，这优于大多数先前报道的非贵金属HER电催化剂。理论计算表明，反应性微环境由两个相邻的SA Mo原子和两个周围对称的Se空位组成，产生了最佳的水离解和氢脱附动力学。这项研究为提高其他基面含有惰性原子的TMDCs的电催化活性提供了一种可扩展的策略。
