High-density single-atom electrocatalytic centers on two-dimensional topological platinum tellurides with Te-vacancy superstructure
cond-mat.mtrl-sci
/ Authors
Xin Xu, Xuechun Wang, Shuming Yu, Chenhui Wang, Guowei Liu, Hao Li, Jiangang Yang, Jing Li, Tao Sun, Xiao Hai
and 13 more authors
Lei Li, Xue Liu, Ying Zhang, Weifeng Zhang, Quan Zhang, Kedong Wang, Nan Xu, Yaping Ma, Fangfei Ming, Ping Cui, Jiong Lu, Zhenyu Zhang, Xudong Xiao
/ Abstract
Chemical activation of the intrinsically inert basal planes of transition metal dichalcogenides (TMDs) is crucial for developing high-efficiency electrocatalysts for energy technology applications. Here we report the discovery of an efficient TMD-based topological catalyst for hydrogen evolution reaction (HER), containing high-density single-atom reactive centers on a few-layer (7x7)-PtTe2-x superstructure with a Te-vacancy density of x. Compared with pristine Pt(111), PtTe2, and (2x2)-PtTe2-x, (7x7)-PtTe2-x exhibits superior HER performance owing to its substantially increased density of undercoordinated Pt sites, and displays exceptional catalytic stability when operating at high current densities. Our first-principles calculations confirm that multiple types of undercoordinated Pt sites on (7x7)-PtTe2-x exhibit favorable hydrogen adsorption Gibbs free energies, and that the reactive sites can further increase their population upon increasing hydrogen coverage. Both the (2x2)- and (7x7)-PtTe2-x are also shown to possess nontrivial band topology with robust edge states that may further facilitate HER.