Nature is of course remarkably adept at performing carbon capture and conversion through photosynthesis of plants, algae, plankton, and other organisms comprising the biosphere. As scientists investigate new mechanisms for large scale conversion processes to meet the needs of our energy transition, an important pathway to explore is that of artificial photosynthesis, which seeks to emulate the example of nature by using engineered photoelectrochemical systems for synthesis of solar fuels, chemicals, fertilizers, and materials.
Solar-fuel systems employ photoexcitation, chemical transformation, and transport processes to produce fuel. A typical system includes light absorbers integrated with oxidation and reduction catalysts, membrane separators, and water-based electrolyte. Three central chemical reactions are involved in artificial photosynthesis of carbon-containing products: the oxygen evolution reaction (OER), the hydrogen evolution reaction (HER), and the CO2 reduction reaction (CO2RR). Each component of the system must be designed to efficiently utilize sunlight's energy to react water and CO2 and produce fuel.
