“…Heterogeneous or homogeneous electrocatalysts, such as Schiff base complexes, have been used to resolve this problem [11,12]. Moreover, among the possible activators of CO 2 , more attention has been paid to superoxide radical anions, O 2 À [13,14]. The O 2 À produced by the electroreduction of O 2 in aprotic solvents activates CO 2 to yield peroxydicarbonate anions, C 2 O 6 2À [13,14].…”