(Keynote) Bioelectrocatalysis of Carbon Dioxide Reduction

Abstract

CO 2 reduction has the potential to address issues related to the environment and the energy crisis. However, the reduction of CO 2 is hard to achieve due to its kinetic and thermodynamic stability. Despite significant research effort, existing catalysts such as transition metals and metal complex suffer from either low selectivity and/or low CO 2 conversion efficiency. Biocatalysts are an attractive alternative owing to their highly selectivity, low overpotential and mild operating conditions. A recently developed molybdenum dependent formate dehydrogenase (Mo-FDH) from Escherichia coli is a biocatalyst that is easy to obtain and has high efficiency to interconvert formate and CO 2 . However, the direct electron transfer of Mo-FDH is inefficient, and so far, no immobilized mediating system has been designed with Mo-FDH to support CO 2 reduction. Low potential redox polymers are rare due to a limited number of mediators and stability issues. Here we developed a reductive redox polymer (cobaltocene modified poly allyl amine; Cc-PAA) to wire Mo-FDH at carbon electrode surfaces and simultaneously mediate electrons to facilitate the CO 2 reduction. The polymer film shows good stability and formate was the exclusive product. This electroenzymatic interface is able to reduce CO 2 to formate at a mild applied potential (-0.66 V. vs SHE) with a high Faradaic efficiency (99 ± 5%).

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Identifiers

DOI

10.1149/ma2020-02633228mtgabs

Journal

ECS Meeting Abstracts

Year

2020