碳纳米管表面Co/MoSe2莫特-肖特基异质结的构筑及高效析氢性能  

Mott-Schottky heterojunction formation between Co and MoSe2 on carbon nanotubes for superior hydrogen evolution

作　　者：任先培 胡启威 凌芳 吴飞 李强[1] 庞柳青 REN Xian-pei;HU Qi-wei;LING Fang;WU Fei;LI Qiang;PANG Liu-qing(School of Physics and Electronic Engineering,Sichuan University of Science and Engineering,Zigong 643000,China;The First Monitoring and Application Center,CEA,Tianjin 300180,China;Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education),College of Chemistry,Nankai University,Tianjin 300071,China)

机构地区：[1]四川轻化工大学物理与电子工程学院,四川自贡643000 [2]中国地震局第一监测中心,天津300071 [3]南开大学先进能源材料化学教育部重点实验室,天津300071

出　　处：《新型炭材料（中英文）》2023年第6期1059-1069,共11页New Carbon Materials

基　　金：四川省自然科学基金项目(22NSFSC0335);DICP催化国家重点实验室项目(N-22-14).

摘　　要：二硒化钼(MoSe_(2))是一种先进的电解水制氢催化剂,但其电催化性能还远不如金属铂(Pt)。将半导体与金属结合构建莫特-肖特基异质结是一种提高催化活性的有效途径。本文采用溶胶-凝胶工艺和热还原法在碳纳米管表面制备了金属钴(Co)/半导体MoSe_(2)莫特-肖特基异质结(Co/MoSe_(2)@CNT)。实验和理论计算结果表明Co/MoSe_(2)莫特-肖特基异质结导致电子在界面处重新分布并形成一个内建电场,这不仅可以优化氢原子吸附的自由能,还可以提高析氢过程中电荷的传输效率。因此,Co/MoSe_(2)@CNT获得了优异的析氢活性:在电流密度为10 mA cm^(-2)时的过电势仅为185 mV、Tafel斜率为69 mV dec^(-1)。这项工作提供了一种新的策略来制备Co/MoSe_(2)莫特-肖特基异质结,并突出了莫特-肖特基效应的重要意义,有利于未来开发出更高效的莫特-肖特基电催化剂。Molybdenum selenide(MoSe_(2))has been regarded as an advanced electrocatalyst for the hydrogen evolution reaction(HER).However,its electrocatalytic performance is far inferior to platinum(Pt).Combining semiconductors with metals to con-struct Mott-Schottky heterojunctions has been considered as an effective method to enhance HER activity.In this work,we report a typical Mott-Schottky heterojunction composed of metal Co and semiconductor MoSe_(2)on carbon nanotubes(Co/MoSe_(2)@CNT),pre-pared by a sol-gel process followed by thermal reduction.The characterization and theoretical calculations show that a Co/MoSe_(2)Mott-Schottky heterojunction can cause electron redistribution at the interface and form a built-in electric field,which not only op-timizes the free energy of hydrogen atom adsorption,but also improves the charge transfer efficiency during hydrogen evolution.Thus,the Co/MoSe_(2)@CNT has excellent catalytic activity with a low overpotential of 185 mV at 10 mA cm^(-2)and a small Tafel slope of 69 mV dec^(-1).This work provides a new strategy for constructing Co/MoSe_(2)Mott-Schottky heterojunctions and highlights the Mott-Schottky effect,which may inspire the future development of more attractive Mott-Schottky electrocatalysts for H2 production.

关 键 词：二硒化钼 钴纳米粒子 莫特-肖特基异质结 析氢反应 

分 类 号：TQ127.11[化学工程—无机化工]