▎ 摘　　要

The present article describes an efficient photo-electrode material consisting of cobalt phthalocyanine tetrasulfonamide (CoPcS) chemically attached to carboxylated graphene oxide (GO-COOH) for a photoelectrochemical CO2 reduction reaction (PEC CO2RR). The chemical attachment of CoPcS complex units to the carboxylated GO support provided a proficient interface for the adsorption of CO2 and enhanced CO2 concentration for higher conversion. In the present study, we achieved high current density (-1.5 mA/cm(2)) at a voltage of -1.0 V vs Ag/AgCl under simulated sunlight with the selective formation of formate at a rate of 2.35 mmol h(-)(1) cm(-2). The photocurrent density of hybrid CoPcS/GO-COOH was found to be reasonably higher than those of pristine CoPcS and GO-COOH. However, AC impedance (EIS) indicated significantly increased charge carriers and decreased e-/h+ pair recombination in the hybrid system. Moreover, the developed hybrid molecular system exhibited improved PEC CO2RR compared to several existing systems. Overall, the results are supported by DFT calculations. A significant overlapping in the electronic bands of hybrid CoPcS/GO-COOH indexed by the density of states (DOS) led to the high PEC conversion.