Hexagonal Layer Manganese Metal-Organic Framework for Photocatalytic CO₂ Cycloaddition Reaction

A novel manganese metal-organic framework (Mn-MOF) termed UAEU-50 assembled from a benzenedicarboxylate linker (BDC) and trinuclear manganese clusters was synthesized and fully characterized using different spectroscopic and analytic techniques (e.g., X-ray powder diffraction, UV-vis diffuse reflectance spectroscopy, thermogravimetric analysis, scanning electron microscopy, and energy-dispersive X-ray spectroscopy). UAEU-50 adopted a hexagonal layer structure and exhibited superior thermal stability and robust chemical stability. Photocatalytic activities of UAEU-50 were investigated using the cycloaddition of CO₂ to different epoxides, forming cyclic carbonates. Impressively, UAEU-50 can transform up to 90% photocatalytic CO₂ conversion to cyclic carbonates in the visible-light region at ambient conditions.