Nanoparticles of PdAu Alloys on BiOBr Nanosheets for Highly Efficient Photocatalytic Suzuki–Miyaura Reactions

Abstract

A series of nanoparticles of PdAu alloy-decorated BiOBr nanosheet self-assembled hierarchical microspheres were successfully synthesized for the photocatalytic Suzuki–Miyaura reaction with high activity and nice recyclability. Compared with BiOBr, the photocatalyst Pd93Au7/BiOBr greatly narrows the energy gap and enhances the light absorption in both ultraviolet (UV) and visible ranges, and the photoinduced electrons transfer from BiOBr to Pd species; the existence of trace amounts of gold in the form of PdAu alloy, as a cocatalyst with strong localized surface plasmon resonance (LSPR) effect, facilitates the electron transfer to Pd active sites and enhances the separation efficiency of photoinduced charge carriers; finally, the enrichment of electrons on Pd sites leads to high photocatalytic performance. Under the optimum reaction conditions, Pd93Au7/BiOBr was demonstrated to be an efficient catalyst for the Suzuki–Miyaura reaction between aryl iodides and aryl boronic acids. Furthermore, in the Suzuki–Miyaura reactions of iodobenzene and phenylboronic acid, there is no obvious decrease in catalytic activity even after six cycles, and the yield of biphenyl remained at 90%.