Assemblies of MXene and Metal-Organic Polyhedra with Post-Functionalized Re(I) Sites for Selective CO2 Photoreduction.

Metal-organic polyhedra (MOPs) are promising building blocks for porous materials, but their use in association with 2D materials is still largely unexplored. Here, we have synthesized novel microporous MOPs-MXene assemblies by simply mixing cationic Zr-based MOP with negatively charged, surface-functionalized MXenes. The composite MOP-MXene was further functionalized with Re(I) (designated as ZrMOP(Re)-MXene) to enable the selective photocatalytic reduction of CO2. ZrMOP(Re)-MXene showed good performance as a heterogeneous photocatalyst without the addition of an external photosensitizer, achieving a turnover number (TON) of 51 and an excellent selectivity of 93% for CO. The integration with MXene serves as an efficient electron transport mediator within the assembly, resulting in TONs being 4.5 and 7 times higher than those of the homogeneous controls of ZrMOP(Re) and [Re(bpy)(CO)3Cl], respectively.