Rational Design of Highly Phosphorescent Nanoclusters for Efficient Photocatalytic Oxidation

Analyzing the molecular structure-photophysical property correlations of metal nanoclusters to accomplish function-oriented photocatalysis could be challenging. Here, the selective heteroatom alloying has been exploited to a Au nanocluster, making up a structure-correlated nanocluster series, including homogold Au, bimetallic AgAu and CuAu, trimetallic AgCuAu, and tetrametallic PtAgCuAu. Their structure-dependent photophysical properties were investigated due to the atomically precise structures of these nanoclusters. Cu-alloyed CuAu showed intense phosphorescence and the highest singlet oxygen production efficiency. Moreover, the generation of ¹O₂ species from excited nanoclusters enabled CuAu as a suitable catalyst for efficient photocatalytic oxidation of silyl enol ethers to produce α,β-unsaturated carbonyl compounds. The generality and applicability of the CuAu catalysts toward different photocatalytic oxidations were assessed. Overall, this study presents an intriguing Au-based cluster series enabling an atomic-level understanding of structure-photophysical property correlations, which hopefully provides guidance for the fabrication of cluster-based catalysts with customized photocatalytic performance.