Au11Ag6 nanocluster: Controllable preparation, structural determination, and optical property investigation

Abstract

The structure/composition of nanoclusters has a decisive influence on their physicochemical properties. In this work, we obtained two different Au–Ag nanoclusters, [Au9Ag12(SAdm)4(dppm)6Cl6]3+ and Au11Ag6(dppm)4(SAdm)4(CN)4, via controlling the Au/Ag molar ratios by a one-pot synthetic approach. The structure of nanoclusters was confirmed and testified by single-crystal x-ray diffraction, electrospray ionization time-of-flight mass spectrometry, XPS, powder x-ray diffraction, and electron paramagnetic resonance. The Au11Ag6 nanocluster possessed a M13 core caped by four Au atoms and four dppm and four AdmS ligands. Interestingly, four CN are observed to locate at the equator of the M13 core. Both nanoclusters contain a similar icosahedral M13 core, whereas their surface structures are totally different. However, the Au11Ag6 nanocluster exhibits good stability and strong red photoluminescence in solution.

Optical Activity from Anisotropic-Nanocluster-Assembled Supercrystals in Achiral Crystallographic Point Groups

“…We also measured several other luminescent nanocluster supercrystals of achiral space groups and successfully detected their polarized PL, demonstrating the universality of the above conclusion. Specifically, the nanocluster supercrystals in achiral point group 1̅ (Au 2 Cu 6 (SAdm) 6 ­(TFPP) 2 and [Au x Ag 9– x (SAdm) 6 ­(Dppm) 2 ]­(SbF 6 ) , ) displayed strong polarized PL, while those in low-symmetry point group 2/ m ([Cu 11 (TBBT) 9 (TPP) 6 ] 2+ , Au 11 Ag 6 (Adm) 4 ­(Dppm) 4 (CN) 4 , and [PtAg 28 (SAdm) 18 ­(TPP) 4 ] 2+ ) exhibited weak polarized PL (Figures S6–S10). By comparison, the [Ag 29 (BDT) 12 (TPP) 4 ] 3– nanocluster in space group Pa (point group m ) with mirror symmetry was unpolarized in PL (Figure S11).…”

Synthesis of Vitamin B1-Stabilized Gold Nanoclusters with High Quantum Yields for Application as Sensors

“…Furthermore, different kinds of strategies have also been developed to enhance the QY of AuNCs, such as changing the protecting ligands, modulating the synthetic approaches, doping them with other atoms, ligand exchange, controllable oxidation, and so forth. − These methods have been proven to effectively enhance the QY of AuNCs. For example, Aldeek and co-workers proposed a ligand exchange methodology, which can result in a 4-fold enhancement QY of AuNCs from 3.5% to ca.…”

Galvanic replacement-induced introduction of a heteroligand into bimetallic and trimetallic nanoclusters

“…Taking into account that Pt(0), Ag(0) and Au(0) provide 0, 1 and 1 electrons to the cluster count, respectively, and that the dtp ligands are formally anionic, both 1 and 2 are 8-electron NCs. To our knowledge, 8-electron M 17 28–31 and M 16 32,33 NCs have been rarely reported compared to the large family of M 25 8-electron systems.…”