Density functional theory study of transition metal dual-atom anchored phthalocyanine as high-performance electrocatalysts for carbon dioxide reduction reaction

Abstract

The electrocatalytic reduction of carbon dioxide (CO2RR) to valuable chemicals provides as a promising approach to reduce the excessive CO2 gas, but the scaling relationship between adsorbed intermediates on catalysts with single active site limits the catalytic activity. The introduction of secondary sites is expected to be an effective way to break this linear relationship to achieve high-performance. Therefore, we designed 28 homonuclear and 18 heteronuclear dual-atom catalyst in rectangular-shaped expanded phthalocyanine (Pc) to explore their CO2RR catalytic activities. After density functional theory screening of catalyst stability, activity and selectivity, FeTi@Pc was identified as an ideal catalyst for the deep reduction of CO2 to CH4 with low limiting potential of −0.18 V. Analysis shows the introduction of Fe heteroatom to homonuclear Ti2@Pc leads to the polarization of the electronic structure, which helps to adjust the binding strength with C and O atom of intermediates. The adsorption configuration and projected density of state of *CHO further confirm that heteronuclear bimetal centers can effectively provide the adsorption sites and synergistically adjust the adsorption intensity for C and O, thereby enhancing the catalytic activity. Finally, this study provides valuable theoretical guidance for the development of efficient CO2RR catalysts with multiple active centers.