Utilizing mixed-linker zirconium based metal-organic frameworks to enhance the visible light photocatalytic oxidation of alcohol

Abstract

A series of mixed-linker zirconium-based metal-organic frameworks (Zr-MOFs) have been synthesized in one-pot reactions. The Zr-MOFs, containing 2-amino-1,4-benzenedicarboxylate (NH2-BDC) as the primary linker and 2-X-1,4-bezenedicarboxylate (X-BDC, X=H, F, Cl, Br) as a secondary linker, have been used as visible light photocatalysts. The incorporation of multi-functional groups into the catalysts was characterized by PXRD, STEM, NMR, N2 physisorption, diffuse reflectance FTIR, and diffuse reflectance UV–vis. The effects of different linkers on the photocatalytic property of the Zr-MOFs were evaluated in the oxidation of benzyl alcohol. The photocatalytic oxidation reaction was performed using a 26W helical bulb as the visible light source, and the temperature of the reaction was kept at 80°C. The Zr-MOF containing mixed NH2-BDC and F-BDC linkers gives five times more conversion in the oxidation of benzyl alcohol compared to the Zr-MOF made of mixed NH2-BDC and H-BDC linkers. We only observed partial oxidation product, benzaldehyde, from the photocatalytic oxidation reaction.