Rational design of CdS/Ce-UiO-66 heterostructure for high-efficiency photocatalytic oxidation of amines to imines

The development of metal-organic framework (MOF)-based composite systems for visible-light-driven organic photocatalysis under mild conditions, offering an effective approach for sustainable and efficient chemical synthesis. Herein, we synthesized Z-scheme photocatalysts CdS/Ce-UiO-66 by combining the representative photocatalyst CdS and Ce-UiO-66, demonstrating excellent photocatalytic performance for imines synthesis in air. The CdS/Ce-UiO-66 composites demonstrated significantly enhanced photocatalytic activity for the oxidative coupling of amines under visible-light irradiation in air, outperforming their individual components. Remarkably, the composite achieved conversion of benzylamine with exclusive formation of imines as the sole product and efficiency up to 84 % at least four cycles. Furthermore, the photocatalytic system exhibited excellent substrate adaptability, demonstrating broad applicability across various amine substrates. The enhanced photocatalytic performance of CdS/Ce-UiO-66 composites can be primarily attributed to the uniform dispersion of CdS nanoparticles and the unique heterostructure system that effectively modulates the band gap, extends the light absorption range, and promotes charge carrier separation. This study not only presents an efficient photocatalytic strategy for the direct synthesis of imines through oxidative coupling of amines but also demonstrates the significant potential of photoactive CdS/MOF hybrid systems in sustainable chemical synthesis.