Size disproportionation among nanocluster transformations

Abstract

Controllable transformation is a prerequisite to the in-depth understanding of structure evolution mechanisms and structure–property correlations at the atomic level. Most transformation cases direct the directional evolution of nanocluster sizes, i.e., size-maintained, size-increased, or size-reduced transformation, while size disproportionation was rarely reported. Here, we report the Au-doping-induced size disproportionation of nanocluster transformation. Slight Au-doping on the bimetallic (AgCu)₄₃ nanocluster produced its trimetallic derivative, (AuAgCu)₄₃, following a size-maintained transformation. By comparison, the (AgCu)₄₃ nanocluster underwent a size-disproportionation transformation under heavy Au alloying, leading to the formation of size-reduced (AuAgCu)₃₃ and size-increased (AuAgCu)₅₆ nanoclusters simultaneously. Such a size disproportionation among the nanocluster transformations was verified by the thin-layer chromatography analysis. This work presented a novel nanocluster transformation case with a size disproportionation characteristic, expected to provide guidance for the understanding of cluster size evolutions.