文献类型：期刊文献

英文题名：Theory-guided design of Pd/C nanocomposite for H2 sensing at room-temperature

作者：Gao, Yang[1];Lu, Qiao[1];Yan, Peijian[1];Tian, Pengfei[1];Zhu, Minghui[2];Xiao, Biao[3];Xuan, Fuzhen[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Key Lab Pressure Syst & Safety, Minist Educ, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem Engn, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[3]Shanghai Inst Special Equipment Inspect & Tech Re, Shanghai 200062, Peoples R China

年份：2022

卷号：581

外文期刊名：APPLIED SURFACE SCIENCE

收录：;EI(收录号：20220211440783);WOS:【SCI-EXPANDED(收录号:WOS:000762841800003)】；

基金：This project was supported by the National Natural Science Foundation of China (Grant Nos. 51835003, 61804054 and 21808057), and the Open Project Program of Wuhan National Laboratory for Optoelec-tronics NO.2020WNLOKF007.

语种：英文

外文关键词：Palladium; Hydrogen gas sensor; Theoretical calculation; Rational design; Structure-performance relationship

摘要：Palladium (Pd) has attracted widespread attention in the application of hydrogen gas (H-2) sensors. Understanding the effect of surface structure on H-2 activation is central to controlling H-2 sensing performance. Here we use density functional theory (DFT) to investigate the adsorption and activation of H-2 on Pd surfaces including (100), (110) and (1 1 1). The most stable adsorption configuration of H-2 with the lowest dissociative adsorption energy of -0.960 eV and the charge transfer of -0.126 e from Pd to H was found on the hexagonal close-packed (hcp) site of Pd(1 1 1), suggesting that Pd(1 1 1) is most favorable for hydrogen sensing. Consistent with theoretical predication, the designed Pd nano-octahedrons enclosed by Pd(1 1 1) facets, which was synthesized by solution reduction method and characterized by multi-techniques including field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM), manifested a high sensitivity of 0.1%, a short response/recover time of 35.5/40.2 s to 4000 ppm H-2 and great stability (15 cycles towards 4000 ppm H-2). Accordingly, we propose that the facile dissociative adsorption of H-2 on Pd(1 1 1) contributes to the readily formation of PdHx and the rapid resistance change, thus leading to the superior performance for H-2 sensing.