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

Electrocatalytic CO 2 reduction reaction (CO 2 RR) is a very prospective strategy to reduce CO 2 to valuable fuels and chemical products, thereby alleviating the growing energy crisis and greenhouse effect. In this study, CO 2 RR 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 CH 3 OH 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 CH 4 , 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 CO 2 RR catalyst. Moreover, the improvement of CO 2 RR 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.