Enhanced Electrochemical CO2 Reduction Using DNA-Based Nanomaterials

Abstract

Carbon dioxide can be converted to high value chemical products. Small molecules have been demonstrated to catalyze electrochemical CO2 reduction (ECR) process. To apply them in a controlled manner, these catalysts are required to be proximal to an electrode surface for the reaction to proceed. We developed a general method to readily place molecular catalysts on electrodes using DNA hybridization-based immobilization. DNA-catalyst complexes were synthesized through an optimized conjugation method and immobilized on screen-printed carbon electrodes and carbon paper electrodes using DNA hybridization. We found that this immobilization method improved the catalytic efficiency of molecular ECR catalysts for both an iron and a cobalt porphyrin-based catalyst. Importantly, DNA-modified catalysts demonstrated higher stability than their unmodified counterparts. Using this method, we could specifically control the distance between the catalytic sites to assemble DNA-catalyst nanostructures and elucidate the structure and function relationship of CO2 electroreduction process. This method affords tunability and specificity, providing a new strategy to improve electrochemical CO2 reduction efficiency.