Two‐Dimensional Perovskites for Photocatalytic CO2 Reduction

The photocatalytic conversion of Carbon dioxide (CO2) into valuable chemicals is one of the most promising approaches for addressing the CO2 emission problem. However, several issues still need to be resolved to increase the efficiency of photocatalytic reaction. Perovskites possess superior light absorption capacity, tunable band gap, high defect tolerance, and diverse dimensionality. Among them, two-dimensional (2D) perovskites are more stable under photocatalytic conditions and have an exciting excitonic characteristics compared to three-dimensional (3D) perovskites. 2D perovskites have unique physical and chemical properties, such as, high stability, polaron formation, quantum well structures, and high exciton binding energies, which remain underexplored for photocatalytic CO2 reduction (pCO2RR). Tuning of these properties is easier in 2D perovskites than 3D perovskites by varying the layer thickness and spacer cations. Therefore, 2D perovskites photocatalysts are emerging as promising materials for reducing CO2 into valuable products. This review discusses the classification and synthesis methods for 2D perovskites, the unique properties that make it favorable for photocatalysis, and recent advances in applying 2D perovskites for pCO2RR by monitoring the operational methodology. It also emphasizes potential for future developments in photocatalysis using 2D perovskites.