Electrochemical CO2 Reduction On Two-Dimensional Metal 1,3,5-triamino-2,4,6-Benzenetriol Frameworks: A Density Functional Study

Electrocatalytic CO2 reduction reaction (CO2RR) is a very prospective strategy to reduce CO2 to valuable fuels and chemical products, thereby alleviating the growing energy crisis and greenhouse effect. In this study, CO2RR mechanisms on M-3(TABTO)(2) (M = Sc-Cu, Y-Mo and Ru-Rh, TABTO = 1,3,5-triamino-2,4,6-benzenetriol) are investigated by means of density functional method. The results show that the studied catalysts are stable thermodynamically. Co-3(TABTO)(2) exhibits the best catalytic performance for the formation of CH3OH with the same overpotential of 0.41 V both in the gas phase and in solution. For Fe-3(TABTO)(2), however, the product is HCOOH with the overpotential of 0.29 V in the gas phase and 0.70 V in solution. For Ru-3(TABTO)(2) to produce CH4, solvent effect reduces the overpotential significantly from 0.97 V in the gas phase to 0.54 V in solution, making it to be a promising CO2RR catalyst. Moreover, the improvement of CO2RR catalyst activity can be achieved by the axial oxygen modification in M-3(TABTO)(2) (M = Sc, Y and V). A good relationship between d band center and overpotential is observed, which might provide us with a new direction to design the promising catalyst. (c) 2022 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.