Synthesis of Highly Fluorescent Silver Clusters on Gold(I) Surface

Abstract

Evolution of fluorescence from a giant core-shell particle is new and synergistic, which requires both gold and silver ions in an appropriate ratio in glutathione (GSH) solution. The formation of highly fluorescent Ag(2)/Ag(3) clusters on the surface of Au(I) assembly results in giant Au(I)(core)-Ag(0)(shell) water-soluble microparticles (~500 nm). Here, Au(I) acts as the template for the generation of fluorescent Ag clusters. The presence of gold under the synthetic strategy is selective, and no other metal supports such synergistic evolution. The core-shell particle exhibits stable and static emission (emission maximum, 565 nm; quantum yield, 4.6%; and stroke shift, 179 nm) with an average lifetime of ~25 ns. The drift of electron density by the Au(I) core presumably enhances the fluorescence. The positively charged core offers unprecedented long-term stability to the microparticles in aqueous GSH solution.

Fuel mediated solution combustion synthesis of ZnO supported gold clusters and nanoparticles and their catalytic activity and in vitro cytotoxicity

“…[1][2][3] Such smaller nanoparticles which are made up of a few to a hundred atoms per particle are termed atomic clusters. Compared to bulk nanomaterials, clusters have a larger number of atoms on the surface of the composites.…”

Photoproduced Fluorescent Au(I)@(Ag2/Ag3)-Thiolate Giant Cluster: An Intriguing Sensing Platform for DMSO and Pb(II)

“…A large amount of silver in EDAX analyses reveals that silver is present in large quantity at the surface ( Figure 9A). 8 Fluorescence microscopic images also display bright, dull, and again bright fluorescence for AuAgF, DAuAgF, and YPPT, respectively ( Figure 9B). XPS spectra of the AuAgF solution under freeze-drying conditions demonstrate peaks at 368.07 and 374.07 eV for silver.…”

“…Further shift of binding energies toward a higher value (369.09 and 375.10 eV, respectively) as well as 50 Sulfur is in the +2 oxidation state in all three cases (∼163.6 eV binding energy is for S(II)2P 3/2 ) ( Figure 9C). 8 Along with the absorption spectra of AuAgF, absorption spectra of DAuAgF, YPPT, and YPPT +Na 2 -EDTA have also been presented in Figure S4 (Supporting Information). In any case, the plasmon band of metals is not observed.…”

“…Though Au clusters have been comprehensively investigated for the ease of preparation and chemical stability, fluorescent Ag clusters are coming in a big way as a promising probe due to stronger fluorescence than Au clusters. 7,8 To date, stable fluorescent silver clusters synthesis is a great challenge. Only a few groups have reported stable fluorescent silver clusters using different synthetic tricks.…”

Selective detection of Mg2+ ions via enhanced fluorescence emission using Au–DNA nanocomposites

“…3, which reveal the formation of Au–DNA NCs [29]. These AuNSs were found to be separated from each other due to the CTAB coating on their surface, which renders them to have a positive charge [30].…”