Covalent Organic Framework-Bacteria Cascades for Sustainable Carbon Dioxide Reduction

Artificial photosynthesis has though paved the way forward towards sustainable and clean energy, the progress has been often impeded by inefficient catalysis as well as costly and toxic materials. However, nature has been pursuing sunlight driven complicated chemical transformation with high selectivity and accuracy. Yet, such catalytic prowess is mostly restricted to naturally occurring reactions that are inefficient for practical application. Toward that end, integrating the strength of natural and artificial photosynthesis would capitalize on the most salient attributes of each component for efficient solar-to-chemical conversion. Herein, we have designed a covalent organic framework-bacteria biohybrid to catalyze carbon dioxide reduction reaction to acetate formation. A photo-sheet (COF|IO- ITO|polythiophenes:RuO2) combined with Sporomusa ovata bacteria would harness solar energy for selective acetate production using only carbon dioxide and water. The process would offer the much-desired sustainability as it will operate without sacrificial reagent or external voltage. The judicious selection of the cascades; microbes (produces carbon products in presence of hydrogen and carbon dioxide), phthalocyanine- porphyrin-based COF (produces hydrogen from water), Ruthenium oxide (RuO2) (for water oxidation) and polythiophenes (integrates anodes into ITO surface) would guarantee high efficiency of the system. The cost effectiveness and scale-up opportunities will lead to the practical deployment of a prototype.