Highly effective photoreduction of CO₂ to CO promoted by integration of CdS with molecular redox catalysts through metal-organic frameworks

We propose a strategy to synthesize ternary CdS/UiO-bpy/Co composites by integration of CdS and molecular redox catalysts through metal-organic framework (MOF) UiO-bpy. The CdS/UiO-bpy/Co composites were very effective for photocatalytic conversion of CO₂ to CO under visible light irradiation. The evolution rate of CO could reach 235 μmol g^-1 h^-1, which was a 10.2-fold improvement compared to that for the parent CdS, and selectivity for CO was 85%. The outstanding performance of the CdS/UiO-bpy/Co composites resulted from promoting the separation and migration of photo-induced charge carriers, enhancing the adsorption of CO₂ molecules, and offering abundant active sites for CO₂ reduction. As far as we know, this is the first study to integrate inorganic semiconductors and molecular redox catalysts through MOFs.