Structures And Properties Of Silver-base Nanoclusters Synthesized By Adamantane Thiol/tertiary Butyl Mercaptan

Due to its excellent properties,atom-precise metallic nanoclusters have attracted extensive research in nanoscience as a new type of nanomaterials.To deeper understand the properties and applications of nanoclusters,the synthesis and characterization of nanoclusters are important.Precise control of synthetic nanoclusters at the atomic level has been the focus of research.The interaction between various ligands can effectively change the surface environment,protecting the clusters.At the same time,because of the synergy between metals,alloy clusters tend to have very specific properties.Controlling the position and number of doping atoms for alloy nanoclusters is the key for the property regulation.And it provides an experimental and theoretical basis for exploring how to better design a high catalytic activity cluster catalyst.Thus,if polydentate phosphine ligand and thiolate ligand were used to protect the alloy cluster,can we synthesize some new?The subject will be based on three aspects:1)By controlling the synthesis method,similar silver-based cluster compounds were synthesized.DFT calculation and other testing methods are used to correlate the structure and properties,revealing the regularity of the influence of the structure on the performance;2)Multidentate phosphine ligands are used together with thiolate ligands to protect the alloy clusters,and new nanoclusters are synthesized,which provides new opportunities for the development of new alloy clusters;3)to further expand the synthesis method of the multidentate phosphine-protected gold nanoclusters and gold nanoclusters with precise structure are synthesize,which enrich phosphine ligand-protected cluster;1)Fluorescence-free silver nanoclusters[Ag₆₂S₁₂（SBu^t）₃₂]²⁺ were synthesized by ligand exchange.Meanwhile,we electrochemically converted quantum dots[Ag₆₂S₁₃（SBut）32]⁴⁺ to[Ag₆₂S₁₂（SBu^t）₃₂]²⁺ And[Ag₆₂S₁₃（SBu^t）₃₂]²⁺ was obtained.The femtosecond transient absorption spectroscopy study shows that free electrons can inhibit the charge transfer from ligands to the metal nucleus,leading to fluorescence quenching.And,density functional theory was used to help resolve the transformation process,so we can understand the transformation process,and correlation between structural and properties of silver cluster.2)The structural isomer alloy cluster[Au₉Ag₁₂（SR）₄（Dppm）_6X6]³⁺ was synthesized.At the same time,the structural isomers possess different chirality,which are chiral structure[Au₉Ag₁₂（SR）₄（Dppm）_6X6]³⁺-C and achiral structure[Au₉Ag₁₂（SR）₄（Dppm）_6X6]³⁺-Ac,respectively.The optical enantiomers of chiral structures were successfully separated.This work expands structural structural isomers and promotes the chiral research.3)The[Au₄Ag₅（Dppm）₂（SAdm）₆]（BPh₄）was synthesized and the structure of it was confirmed.Meanwhile,[Au₄Ag₅（Dppm）₂（SAdm）₆]⁺ has an aggregation-induced emission（AIE）property.EXAFS experiments ruled out changes in the structure between the solution and the solid-state.The design of this monodisperse alloy nanocluster will provide a new strategy for high-solid-state luminescence nanocluster and help understand the mechanism of luminescence at atomic-level.4)Two supramolecular clusters were synthesized:Au₂Ag（42）（SAdm）₂₇（BPh₄）and[Au₂Ag₄₈（S-tBu）₂₀（Dppm）₆Br₁₁]Br（BPh₄）₂.The defined structure indicates that both clusters are composed of 8e icosahedral M13 superelements.The implementation of the Kohn-Sham MO allows an understanding of the electronic structure of these supramolecular cluster complexes,whichthe valence electron structure is like the Ne2 molecule.The presence of two ligand-protected supramolecular cluster complexes will enrich the supramolecules and help to gain insight into the super-structural units that can self-assemble into such supramolecules.5)Thiol-induced synthesis of phosphine-protected gold nanoclusters with atomic precision were achieved for[Au]₃（Dppm）₆]³⁺,[Au₁₈（Dppm）₆Br₄]²⁺ and[Au₂₀（Dppm）₆（CN）₆].Simultaneously,the interesting transformation from[Au₁₈（Dppm）₆Br₄]²⁺ to[Au₁₃（Dppm）₆]³⁺ and[Au₂₀（Dppm）₆（CN）₆]₆]helps us to understand the transformation between clusters more deeply.In addition,[Au_16.1Ag_1.9（Dppm）₆Br₄]²⁺ was synthesized by targeted metal exchange.This research helps us to explore the synthesis of phosphine ligands protected nanocluster and the structural transformation through ligand/metal regulation.