Artificial photosynthesis: (photo)catalysts for CO2 reduction
Storage of solar energy in the form of chemical fuels can be achieved through photoreduction of carbon dioxide into formic acid, methanol, methane or other hydrocarbons in photoelectrochemical cells. These artificial leaves function by absorption of solar photons by a photosensitizer/semiconductor at the photoanode where a catalyst serves to facilitate water oxidation by the holes created in the valence band. The excited electron in the conduction band is transferred to the cathode or the photocathode where it reduces CO2. The last reaction, a multielectronic process as well, requests an efficient and selective catalyst. Currently both solid materials and molecular compounds are developed as catalysts for CO2 reduction. During this presentation, an overview of the best and most recent electrocatalysts and photocatalysts will be presented.