Researchers have created a solar-powered catalyst system that uses the energy of a single photon to reduce carbon dioxide while oxidizing organic waste at the same time. The process yields useful chemicals from both reactions.
Scientists at the University of Nottingham developed two catalyst materials placed in separate compartments of a photoelectrochemical reactor. Sunlight striking one compartment drives the oxidation of a biowaste molecule. The released electron travels to the second compartment, where it reduces CO2 into formate.
This produces two valuable outputs from one photon: formate, a chemical used in textiles, paints and pharmaceuticals, and a precursor for bio-based plastics made from waste.
The reactor achieved about 93 percent efficiency in converting CO2 to formate and roughly 95 percent efficiency in biomass oxidation. Because the reactions run on sunlight alone, without added heat or electricity, the method offers a route to low-carbon chemical production.
The catalysts are made from earth-abundant elements rather than scarce metals. A life-cycle assessment confirmed environmental advantages, supporting potential scale-up for industrial use. The team previously used similar on-surface assembly techniques to make catalysts for hydrogen production and methanol synthesis from CO2.
Future work aims to link the system with industrial CO2 sources and biorefineries for distributed, sustainable manufacturing.
