Salen ligand complexes as electrocatalysts for direct electrochemical reduction of gaseous carbon dioxide to value added products

CO2, being a linear and centrosymmetric molecule, is very stable, and the electrochemical reduction of CO2 requires energy. Moreover, the CO2 electroreduction proceeds at a significantly higher applied voltage than thermodynamically required. In this concern, salen ligand, H2LNO2, and its corresponding Ni(II) and Cu(II) complexes are synthesized and reported for the first time as electrocatalysts for CO2 electroreduction. Both the metal complexes are active for CO2 reduction and surprisingly result in formation of C1 and C2 hydrocarbons. The complexes are found to be very efficient to minimize overpotential required for the reaction as compared to their pure metal counterparts. Thus, the present study opens up a new class of metal complexes for the efficient electrochemical reduction of CO2 having the potential to generate hydrocarbons at lower overpotentials.