Bio-inspired CO2 reduction reaction catalysis using soft-oxometalates.

ABSTRACT

The enzyme, Formate Dehydrogenase, is biological catalyst responsible for the hydrogenation of carbon dioxide to formic acid. The present research has discovered CO2 reduction activities and their application using certain metal containing (Mo- or W-)/ NAD + -linked Formate Dehydrogenases. However, the enzyme must be immobilized for easy separation, increased stability and reusability. The shortcomings associated with conventional immobilization method include leaching, mass transfer limitation and low activity. We here present a perspective, wherein, we assess the efficacy of soft-oxometalates and macrocycles as a promising alternative to Formate Dehydrogenase immobilization. The mechanistic pathway and stability of Formate Dehydrogenase from different sources are discussed and compared with their tailored 'chemical counterparts' soft-oxometalates and macrocycles based systems such as {Mo132}, {Mo154}, {MoV9}, Co and Mn based Corroles. The structure, properties and mechanism of CO2 reduction by different Soft-oxometalates and metal based macrocycles were found to be synonymous with that of metal based Formate Dehydrogenase. We comprehensively summarize different reported approaches to valorize CO2 to C1 and C2 products such as photochemical, electrochemical and systems chemistry to showcase our efforts in the ongoing pursuit of CO2 valorization, inspired by the workings of such enzymes, alongside the efforts of several other leading groups. The revelatory insights in the perspective could be used not only for developing bio-inspired CO2 Reduction Reaction but also constructing artificial cell automata for artificial life like system.