Stabilizing ultrasmall Au clusters for enhanced photoredox catalysis

Abstract

<p><a></a><a>Recently, loading ligand-protected gold (Au) clusters as visible light photosensitizers onto various supports for </a>photoredox catalysis has attracted considerable attention. However, the efficient control of long-term photostability of Au clusters on the metal-support interface remains challenging. Herein, we report a simple and efficient method for enhancing the photostability of glutathione-protected Au clusters (Au GSH clusters) loaded on the surface of SiO₂ sphere by utilizing multifunctional branched poly-ethylenimine (BPEI) as a <a>surface charge</a> modifying, reducing and stabilizing agent. The sequential coating of thickness controlled TiO₂ shells can further significantly improve the photocatalytic efficiency, while such structurally designed core-shell SiO₂-Au GSH clusters-BPEI@TiO₂ composites maintain high photostability <a></a><a>during</a> longtime light illumination conditions. <a></a><a>This </a>joint strategy <i>via</i> interfacial modification and composition engineering provides<a></a><a> </a>a facile guideline for stabilizing ultrasmall Au clusters and rational design of Au clusters-based composites with improved activity toward targeting applications in photoredox catalysis.</p