Group VB transition metal dichalcogenides for oxygen reduction reaction and strain-enhanced activity governed by p-orbital electrons of chalcogen

查看全文 作　　者：Shuyang [1,2]Zhao;Ke [1,2]Wang;Xiaolong [3]Zou;Lin [1,2]Gan;Hongda [1,2]Du;Chengjun [1,2]Xu;Feiyu [1,2]Kang;Wenhui [4]Duan;Jia [1,2]Li 机构地区：[1]Guangdong Provincial Key Laboratory of Thermal Management Engineering and Materials, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China;[2]Shenzhen Geim Graphene Center, Division of Energy and Environment, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China;[3]Tsinghua-Berkeley Shenzhen Institute (TBSI), Tsinghua University, Shenzhen 518055, China;[4]Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China 出　　处：《Nano Research》索引2019年第12卷第4期,共6页 基　　金：National Key Research and Development Program of China (No. 2017YFB0701600);National Natural Science Foundation of China (Nos. 11874036, 51622103, and 21573123);Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (No. 2017BT01N111);Shenzhen Projects for Basic Research (No. JCYJ20170412171430026);National Program for Thousand Young Talents of China. 摘　　要：Developi ng alter native oxyge n reducti on reactio n (ORR) catalysts to replace precious Pt-based metals with abundant materials is the key challe nge of commercial application of fuel cells. Owing to their various compositi ons and tun able electronic properties, transition metal dichalcogenides (TMDs) have the great potential to realize high-efficiency catalysts for ORR. Here, various 3R-phase dichalcogenides of group VB and VIB transition metals (MX2, M = Nb, Ta, Mo, W;X = S, Se, Te) are investigated for ORR catalysts by using density functional theory calculations. The computed over-potentials of group VB TMDs are much less than those of group VIB TMDs. For group VB TMDs, a volcano-type plot of ORR catalytic activity is established on the adsorption energies of *OH, and NbS2 and TaTe2 exhibit best ORR activity with an oveepotential of 0.54 V. To achieve even better activity, strain engineering is performed to tune ORR catalytic activity, and the minimum over-potential of 0.43 V can be realized. We further dem on strate that the shift of p orbital center of surface chalcoge n elements under strain is responsible for tuning the catalytic activity of TMDs. 关 键 词：transition metal DICHALCOGENIDES fuel cells oxygen reduction reaction STRAIN density functional theory (DFT) CALCULATIONS