A review of the application of wide-bandgap semiconductor photocatalysts for CO2 reduction

Artificial photosynthesis is a viable technique for mitigating the ever-increasing energy demands by converting carbon dioxide (CO2) into energy-rich C1 and C2+ products. A massive contribution to climate change and global warming is the widespread use of fossil fuels, responsible for more than 90% of total CO2 emissions and more than 75% of global greenhouse gas emissions. The most efficient method to convert CO2 into renewable and clean energy is utilizing plentiful sun energy to accelerate photo-induced chemical reactions. Practical CO2 reduction (CO2R), including choosing promising wide-bandgap (WBG) semiconductor photocatalysts with more negative conduction band potential, would be a holy grail for selective fuels and chemicals production. This review article deliberates on the importance of WBG semiconductor photocatalysts and a specific energy level in the conduction band for selective photocatalytic CO2R, which may assist in guiding future photocatalyst design for CO2R. In addition, the summary and prospects of WBG semiconductor photocatalysts and techniques for improving CO2 conversion efficiency and selectivity are discussed.