Incorporation of a Ru complex into an amine-functionalized metal–organic framework for enhanced activity in photocatalytic aerobic benzyl alcohol oxidation

Abstract

The well-defined cavities of metal–organic frameworks (MOFs) offer interesting opportunities for the encapsulation of various nanoparticles, organic dyes and metal complexes. In particular, [Ru(bpy)₃]²⁺-incorporated MOFs (bpy = 2,2′-bipyridine) have been studied because of the high photocatalytic activity of the Ru complex. However, the successful application of this composite in photocatalysis is rarely reported. We herein report the facile encapsulation of [Ru(bpy)₃]²⁺ in MIL-125-NH₂, an MOF composed of 2-aminoterephthalic acid linkers and Ti₈O₈(OH)₄ clusters. The Ru complex-incorporated MOF showed significantly enhanced activity in the photocatalytic aerobic oxidation of benzylalcohol to benzaldehyde as compared to its complex-free and amine-free counterparts. The high activity of the metal complex-incorporated MOF was attributed to the combined visible light absorption by both MIL-125-NH₂ and the [Ru(bpy)₃]²⁺ complex.