Progress in the study of fluorescent Au nanoclusters by Xinjiang Institute of physics and chemistry

Luminescent metal cluster is a kind of small size material (particle size < 3 nm) which is composed of several to dozens of transition metal atoms (such as Au, Ag, Cu, Pt, PD, etc.) Luminescent metal clusters are intermediate "transition states" between atomic metals and metal nanoparticles Preparation of Au nanoclusters with different sizes and their photocatalytic degradation of methylene blue (source: Xinjiang Institute of physical and Chemical Technology) In recent years, metal clusters have attracted extensive attention of researchers due to their excellent photoluminescence properties and high catalytic activity They have shown great application potential and research value in various fields such as chemical catalytic reaction process, biological and chemical detection, fluorescence imaging markers, etc However, due to the high surface activity due to the small size, metal clusters are very easy to aggregate and oxidize Therefore, how to synthesize stable metal clusters with excellent luminescent and catalytic properties is a difficult research work Wang Chuanyi's team, environmental science and technology research office, Xinjiang Institute of physical and chemical technology, Chinese Academy of Sciences, used a silane coupling agent (3-Mercaptopropyltrimethoxysilane) as a stabilizer and reducing agent to prepare Au nano clusters with adjustable size and fluorescence by rapid and effective photoreduction The ratio of stabilizer and Au precursor can be simply adjusted to adjust the emission wavelength of the cluster, which varies from 538 to 580 nm In addition, the synthesized Au nanoclusters have relatively long fluorescence lifetime: 34.04 to 46.83 ns; meanwhile, the fluorescence quantum yield of the clusters is as high as 0.26 – 3.16%, which changes with the emission wavelength Compared with bulk gold, the cluster has special electronic structure and semiconductor like properties, such as the absorption edge in UV absorption spectrum In addition, the Au nanoclusters also have a certain photocatalytic ability, and can participate in the photocatalytic reaction independently Under the irradiation of visible light, the cluster can effectively promote the degradation of methylene blue, and the degradation rate of methylene blue reaches 95.6% in 60 minutes This discovery further expands the application of Au nanoclusters in the field of catalysis Relevant research results were published in nanoscale and attracted wide attention of peers The research work was supported by NSFC, the "International Partnership Program of innovation team" and the "Thousand Talents Program" (Xinjiang project) of Chinese Academy of Sciences Paper link: http://pubs.rsc.org/en/content/article landing/2017/nr/c7nr01052d/unauth