Insights into Atom-Level Local Reactions for CO2 Photocatalytic Production: Reaction Pathways and Product Selectivity at the Atomic Level

Artificial photosynthesis of CO2 at various atomic active sites proves an eyes-attaching means with high catalytic efficiency in simultaneously eliminating carbon dioxide and producing valuable chemical feedstocks. However, the distinct reaction pathways and product selectivity among the same types of atomic active sites significantly inhibit the acquirement of the high ratio of the target product from CO2 photosynthesis in practical application. Given this gap, this review pays attention to systemically discussing the effects of the atom-level local reaction centre, including the atomic active sites centred photocatalyst and the local environment, on the affinity to the reactants, the photoelectrons transfer, and the affinity of atomic active sites to the intermediates, such as single atom, vacancy, and frustrated Lewis pairs, in the process of CO2 photoconversion. This work aims to provide instructions for a more profound understanding of the mechanism of artificial photosynthesis, and the reaction pathways at the atomic active sites.