HCOOH Electrosynthesis via Coelectrolytic Processes of CO2 Reduction and CH3OH Oxidation

Electrochemical coconversion of CO2 at the cathode and CH3OH at the anode to produce HCOOH provides a sustainable route for low-cost HCOOH production and efficient utilization of CO2. Catalysts play an important role in electrochemical reactions. However, there are still few efficient matched catalysts for CH3OH oxidation to HCOOH and CO2 reduction to HCOOH (CO2RR-to-HCOOH). Herein, metal-doped LaMnO3 (Ag-LMO, Sn-LMO, and Sr-LMO) for CH3OH oxidation to produce HCOOH at the anode and Cu-M (M = Pd, Pb, Bi, Sn, and In) bimetal catalysts for CO2RR-to-HCOOH at the cathode are exploited. The results indicate that metal-doped LaMnO3 could directly facilitate CH3OH oxidation by reducing the overpotential. The B-site metal-doped effect is better than the A-site metal-doped effect on CH3OH oxidation. B-site metal-doped Ag-LMO exhibits a better CH3OH oxidation performance, which can reduce the Delta GPLS by 43.08% compared to LMO. Pb@Cu shows an excellent catalytic activity for CO2 reduction to HCOOH. The overpotential is 0.08 V for CO2 reduction to HCOOH. This study shed light on the application of Cu-based bimetal materials and La-Mn perovskites in the electrocatalytic field.