Unraveling the Impact of Gold(I)–Thiolate Motifs on the Aggregation‐Induced Emission of Gold Nanoclusters

Abstract

Aggregation‐induced emission (AIE) provides an efficient strategy to synthesize highly luminescent metal nanoclusters (NCs), however, rational control of emission energy and intensity of metal NCs is still challenging. This communication reveals the impact of surface AuI‐thiolate motifs on the AIE properties of Au NCs, by employing a series of water‐soluble glutathione (GSH)‐coordinated Au complexes and NCs as a model ([Au10SR10], [Au15SR13], [Au18SR14], and [Au25SR18]−, SR=thiolate ligand). Spectroscopic investigations show that the emission wavelength of Au NCs is adjustable from visible to the near‐infrared II (NIR‐II) region by controlling the length of the AuI‐SR motifs on the NC surface. Decreasing the length of AuI‐SR motifs also changes the origin of cluster luminescence from AIE‐type phosphorescence to Au0‐core‐dictated fluorescence. This effect becomes more prominent when the degree of aggregation of Au NCs increases in solution.

Luminescent metal nanoclusters: Biosensing strategies and bioimaging applications

“…further studied the influence of Au(I)‐thiolate motifs on the AIE of Au NCs. [48] They systematically studied the AIE behavior of a series of Au(I)‐SR complexes and Au NCs. They found that the emission mechanism of Au NCs is intrinsically affected by the length of Au(I)‐SR motifs.…”

Silver in the Center Enhances Room‐Temperature Phosphorescence of a Platinum Sub‐nanocluster by 18 Times

“…However, in the early investigations, metal nanoclusters had very weak photoluminescence (PL), with quantum yield typically in the order of 0.1 % or less [17, 18] . Designing strategies are needed but the most fundamental issue; the origin of PL remains unclear [19–27] . There has been a considerable controversy surrounding the roles of the metal core (metal–metal interaction) and the shell (metal–ligand interaction).…”

“…[17,18] Designing strategies are needed but the most fundamental issue; the origin of PL remains unclear. [19][20][21][22][23][24][25][26][27] There has been a considerable controversy surrounding the roles of the metal core (metal-metal interaction) and the shell (metal-ligand interaction). In recent studies, several findings have been reported regarding the designing strategies for brighter cluster luminogens.…”

“…In 2012, Xies group reported aggregation-induced emission (AIE) of non-luminescent oligomeric Au I -thiolate complexes into Au 0 @Au I -thiolate clusters, with a PL quantum yield of about 15 %. [28] Since then, AIE in the forms of solutioninduced aggregation of Ag, [29] Au, [27,30] Cu, [31] Au 3 -Ag-Au 3 [32] nanoclusters, self-assembly of Cu, [33] Ag [34] nanoclusters and crystallization of Au-Ag nanoclusters [35] have been reported. Heterometal atom doping has also been successful.…”

Molecular reactivity of thiolate-protected noble metal nanoclusters: synthesis, self-assembly, and applications

“…The remarkable achievements of X-ray crystallography in the past two decades suggest a universal core-shell structure scheme for [M n (SR) m ] q NCs, in which an M(0) core is capped by a monolayer of M(I)-SR protecting motifs. [9][10][11][12][13][14][15][16][17][18] Based on this molecule-like structure and the strong quantum connement effects in this ultra-small size regime, metal NCs exhibit many molecule-like properties, such as HOMO-LUMO transition, 10,12,13,19 strong luminescence, [20][21][22][23] intrinsic chirality, 24 and good catalytic activity. 5,[25][26][27] More intriguingly, almost all these molecule-like properties show an atomic-level dependency on the cluster structure.…”