Elastic strain controlling the activity and selectivity of CO2electroreduction on Cu overlayers

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

View graph of relations

Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)4933-4944
Journal / PublicationJournal of Materials Chemistry A
Volume9
Issue number8
Online published7 Jan 2021
Publication statusPublished - 28 Feb 2021

Abstract

Cu could reduce COinto considerable amounts of hydrocarbons, the relative low efficiency and poor selectivity of which should be improved. Engineering the surface strain is a powerful method to improve the catalytic performance, however, generally clouded by the ensemble effect and ligand effect. In this research, we show how the elastic strain in Cu nanofilms varies the activity and selectivity of CO2RR by virtue of the two-way shape memory effect of the NiTi substrate. For a 32 nm Cu overlayer, tensile strain improved the total CO2RR faradaic efficiency from 65.02% to 76.48% and favored CHgeneration. For a 5 nm Cu overlayer, strain impacted both HER and CO2RR activities, where compressive strain induced more available active sites for COadsorption and resulted in 27% higher faradaic efficiency toward the CO2RR. Based on DFT calculations and the derived positive correlation between free energy change and the energy barrier, the mechanism of strain-controlled electrocatalytic performance was also revealed.