文献类型：期刊文献

英文题名：Direct Z-scheme GaN/WSe2 heterostructure for enhanced photocatalytic water splitting under visible spectrum

作者：Ye, Xiaojun[1];Zhuang, Fangfang[1];Si, Yuhan[1];He, Jingwen[1];Xue, Yifan[1];Li, Hongbo[1];Wang, Kai[2];Hao, Guoqiang[1];Zhang, Rui[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai 200237, Peoples R China;[2]Shanghai Inst Space Power Sources, State Key Lab Space Power & Sources Technol, Shanghai 200245, Peoples R China

年份：2023

卷号：13

期号：29

起止页码：20179

外文期刊名：RSC ADVANCES

收录：;EI(收录号：20233014441228);WOS:【SCI-EXPANDED(收录号:WOS:001019117600001)】；

基金：This work was supported by East China University of Science and Technology (200237). This work was financed by Science and Technology Commission of Shanghai Municipality, China [Grant No. 17DZ1201405].

语种：英文

外文关键词：Carrier mobility - Density functional theory - Electric fields - Electronic properties - Free energy - Gibbs free energy - III-V semiconductors - Selenium compounds - Van der Waals forces

摘要：van der Waals heterostructures are widely used in the field of photocatalysis due to the fact that their properties can be regulated via an external electric field, strain engineering, interface rotation, alloying, doping, etc. to promote the capacity of discrete photogenerated carriers. Herein, we fabricated an innovative heterostructure by piling monolayer GaN on isolated WSe2. Subsequently, a first principles calculation based on density functional theory was performed to verify the two-dimensional GaN/WSe2 heterostructure and explore its interface stability, electronic property, carrier mobility and photocatalytic performance. The results demonstrated that the GaN/WSe2 heterostructure has a direct Z-type band arrangement and possesses a bandgap of 1.66 eV. The built-in electric field is caused by the transfer of positive charge between the WSe2 layers to the GaN layer, directly leading to the segregation of photogenerated electron-hole pairs. The GaN/WSe2 heterostructure has high carrier mobility, which is conducive to the transmission of photogenerated carriers. Furthermore, the Gibbs free energy changes to a negative value and declines continuously during the water splitting reaction into oxygen without supplementary overpotential in a neural environment, satisfying the thermodynamic demands of water splitting. These findings verify the enhanced photocatalytic water splitting under visible light and can be used as the theoretical basis for the practical application of GaN/WSe2 heterostructures.