CO2 electroreduction performance of PtS2 supported single transition metal atoms: a theoretical study.

Abstract

Electrocatalytic CO2 reduction is a sustainable strategy to convert CO2 into valuable carbon products. Atomically dispersed single-atom catalysts (SACs) have great potential as effective electrocatalysts for the CO2 reduction reaction (CO2RR). Transition metal dichalcogenides (TMDs) are considered to be a kind of promising SAC supports. In this work, ten different 3d TM single atoms (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn) embedded in PtS2 with single S-vacancy (TM-PtS2) were designed by density functional theory (DFT) as candidate electrocatalysts for the CO2RR. Possible reaction pathways of CO2 reduction to different C1 products were systematically investigated. The results show that for all these TM-PtS2 SACs, higher selectivity was achieved for CO2 reduction to C1 products than for the competing hydrogen evolution. HCOOH is the most favorable reduction product on PtS2-Sv supported Sc, Ti, V, Cr, Mn, Fe and Cu SACs, while multiple C1 products are generated on Co-, Ni- and Zn-PtS2. In particular, it is found that Sc-, V-, Fe-, Co- and Cu-PtS2 exhibit higher electrocatalytic performance for the CO2RR than Cu(211). Therefore, these five SACs are promising CO2RR electrocatalysts.