Photoelectrochemical and electrochemical carbon dioxide recycling provides an attractive approach to synthesizing fuels and chemical feedstocks using renewable energy. On the path to deploying this technology, basic and applied scientific hurdles remain. Integrating catalytic design with mechanistic understanding yields scientific insights and progresses the technology closer to industrial relevance. Catalysts must be able to generate valuable carbon-based products with better selectivity, lower overpotentials, and improved current densities with extended operation. With catalytic conversion of atmospheric CO2 considered imperative to realize a carbon-neutral society, our group`s research is focused on developing efficient electro- and photocatalytic materials and novel combinatory approaches. In this talk, I will review our recent progress in two frontiers: photosynthetic biohybrids and nanoparticle electrocatalysis. Our photosynthetic biohybrids combine the strengths of inorganic materials and biological catalysts. Such systems exploit semiconductor broadband light absorption to capture solar energy and subsequently transform it into valuable CO2-derived chemicals by taking advantage of the metabolic pathways in living organisms. Importantly, these systems now ascend to the high solar efficiencies of traditional semiconductor-based photovoltaic and photoelectrochemical devices and transfer over the captured sunlight to the robust and selective CO2-fixing microorganisms responsible for the biosynthesis of a diverse, nearly limitless, array of chemical products. Parallel with our bio-photoelectrochemical efforts, three fundamental scales (atomic, nano, and ensemble) dictating electrocatalytic properties of inorganic nanoparticles have been studied in order to develop inorganic electrocatalysts with better selectivity and lower overpotential. Reducing CO2 to complex products, such as hydrocarbons and oxygenates, with multiple electron transfers, has been achieved by controlling the morphological features of a nanoscale catalyst and utilizing an ensemble of nanoparticles as a catalytic platform. Finally, these inorganic nanoparticle electrocatalysts have been integrated with our semiconductor nanowire photocathodes to achieve direct solar driven CO2 fixation.

Bio-photoelectrochemical and electrochemical CO2 reduction

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.