Highly Stable Lanthanide-Organic Frameworks Based on {LnO} Clusters with Photocatalytic Reduction of CO to CO.

Metal-organic frameworks (MOFs) with adjustable structures, diverse chemical functionalities, and excellent CO capture ability have shown important potential application in the photocatalytic reduction of CO to valuable fuel to curb the energy crisis. In this work, a series of new isostructural lanthanide-organic frameworks based on hexanuclear {LnO} clusters, {(DMA) [Ln(μ-OH)(HO)(SBTC)]} (Ln-MOFs, Ln = Eu, Dy, Gd, Tb, Yb; HSBTC = 5,5'-(ethene-1,2-diyl) di-isophthalic acid; DMA = dimethylamine cation) were synthesized by the solvothermal method. Ln-MOFs were metal-organic frameworks formed by {Ln(μ-OH)} clusters and poly(carboxylic acid) ligands HSBTC, which exhibited excellent photocatalytic properties for the reduction of CO to CO. Among these Ln-MOFs, the production rate of photocatalytic reduction of CO to CO by was 663.00 μmol·h·g and the selectivity reached 94.2%, utilizing [Ru(bpy)]Cl·6HO as photosensitizers. Experimental characterizations and density functional theory (DFT) calculations unveiled that the effective charge separation, strong CO binding affinity, weak HO adsorption energy, as well as low reaction energy barriers for the *COOH intermediates over play an important role in possessing superior photoactivity. This study provides insights into the field of Ln-MOF materials for efficient photocatalytic CO reduction and conversion applications.