Elemental-Doped Catalysts for Photoelectrochemical CO₂ Conversion to Solar Fuels

Solar-driven photoelectrochemical (PEC) carbon dioxide (CO₂) conversion to valuable chemicals, combining the advantages of photocatalysis and electrocatalysis, represents a promising approach toward establishing a carbon-neutral society and harnessing solar energy. Photoelectrode materials doped with metals and/or nonmetals have shown promise in achieving high CO₂ reduction efficiency. Metal or nonmetal doping entails introducing a heteroelement into the semiconductor, thereby modifying the band potentials of the semiconductor through the addition of a defective state. This alteration may improve the charge transfer kinetics of the catalysis. Furthermore, doping aids in creating active CO₂ adsorption offers anchoring sites for CO₂ molecules and can promote product selectivity. This review aims to provide a concise summary of elemental-doped photoelectrodes for converting CO₂ into fuels through PEC processes. Several key factors affecting the performance of PEC CO₂ reduction are discussed, including the interaction of reactants with catalysts, reaction conditions, and the impact of the photoelectrode. Moreover, various PEC CO₂ reduction systems are discussed, with a specific focus on enhancing the efficiency of CO₂ reduction. Finally, a summary of key considering aspects for further development of the PEC CO₂ reduction is provided.