摘要
Two-dimensional(2D) materials have exhibited great potential for replacing costly Pt for oxygen reduction reaction(ORR) because of their distinctive structural features and high pre-site activity.However,their performance is generally hindered by the limited density of active sites(e.g.,at the layer edges).Although they feature a high exposure of surface sites,these sites are typically inert for ORR.Herein,through density functional theory calculations,we propose a promising ORR catalyst candidate,a 2D TaTe_(2) nanosheet,which has an intrinsic high basal-plane activity.Both of the thermodynamic and kinetic processes are explored,which demonstrates that the basal-plane Te sites of the TaTe_(2) nanosheet have great potential for facilitating ORR.Specifically,we construct a microkinetic model of ORR proceeding on TaTe_(2),which unveils its dynamic intermediate coverage under different electrode potentials and identifies the dominating associative pathway.The theoretical half-wave potential of TaTe_(2) is predicted to be 0.87 V,which exceeds those of the well-established Pt(111) and Fe–N–C single-atom catalysts computed at the same level.This study not only presents the first 2D,non-Pt ORR catalyst candidate with an intrinsic basal-plane activity but also offers a rational methodology for unveiling the mechanism/activity of ORR and other electrochemical reactions.
基金
financial support from the Nanyang Environment and Water Research Institute (Core Fund), Nanyang Technological University, Singapore。
