Reversible Interconversion between CO2 and Formate using Bis(dithiolene) Tungsten Oxo Complex

Abstract

Reducing and utilizing CO2 present in the atmosphere is a crucial global issue. Electrochemical CO2 reduction has emerged as a promising method for addressing this challenge, but the development of efficient catalysts is still at a preliminary stage. Various approaches have been attempted to develop efficient catalysts, and one of them involves synthesizing complexes that mimic the active sites of enzymes found in nature. While there are many researches on the model complex of enzymes that can reduce CO2, there is limited research on the model complexes of Formate Dehydrogenase (FDH) which is capable of interconverting formate and CO2. Therefore, the reactivity of model complex of FDH will be investigated. Although the formation of bicarbonate intermediate through the reaction of this model complex with CO2 has been reported, there are no studies on the subsequent reactions. Based on these findings, we hypothesized that an electrochemical method could be tried to achieve CO2 reduction using a FDH model complex. We also checked the reactivity about the formate oxidation reaction, which is the forward reaction of FDH, through electrochemical method. Therefore, we investigated the reactivity of each reaction using electrochemical methods and observed the corresponding products. Additionally, through mechanism studies, we gained insights into the subsequent reactions after the formation of bicarbonate intermediate.