Co-synthesis And Performance Study Of Double Crown Ni_n(PET)_2n(n=4,5,6) Nanoclusters Protected By Thiol Ligand

Since Crosse BC first synthesized and analyzed the single crystal structure of Ni₆（SC₂H₅）₁₂ in 1965,Several progress has been achieved in the field of thiolite ligand-protected tiara-like structural metal clusters,such as developed new synthesis routes,obtained the structure and studied the physical and chemical properties of tiara-like Ni_n（SR）_2n（n=4-6,8-12）nanoclusters protected by various mercaptan ligands,as well as a large number of theoretical calculation researchs related to the electronic structures and properties of these nanoclusters.However,due to the interferences of the ligand effect,the synthesies history cannot be ruled out,the study on the evolution of the nickel nanoclusters’structure and properties with the number of nickel atoms is limited.This paper mainly explores and verifies from the following three aspects:1.To explore the synthesis method of atomically controllable tiara-like Ni nanoclusters,the mixture of three Ni_n（PET）_2n（n=4,5,6）nanoclusters was synthesized by one-pot method,in which nickel nitrate reacted with phenylethanethiol（HSC₂H₄Ph,PET）under weak base conditions.Then thin layer chromatography（TLC）was used for the separation of the obtained maxture to obtain a pure series of monodisperse tiara-like Ni_n（PET）_2n（n=4,5,6）clusters,Further the molecular weight,molecular structure and ligand spatial position of these three nanoclusters was characterized.2.The effect of n value on the structure and performance of tiara-like Ni_n（PET）_2n clusters was studied.In this part,we determine the experimental energy gap of nickel nanoclusters by electrochemical（DPV）method and optical absorption.The theoretical gap of the nickel nanoclusters was calculated by density functional theory,and the effects of n value on the light absorption and electrochemical properties of the clusters were further summarized.And found a pseudo optical gap of Ni₄（PET）₈ is contrary to the law.3.On the basis of the host-guest chemical properties of the proposed tiara-like Ni nanoclusters,according to their special cavities and spatial structures,the host-guest chemical properties of the series of Ni nanoclusters are explored,and we find that Ni₆（PET）₁₂ owns unique host-guest chemical properties with inserting a silver ions in its central hole.Based on this,Ni₆（PET）₁₂ has unique advantages and prospects in the field of silver ion-specific recognition due to the 1:1 correspondence between Ni₆（PET）₁₂ and Ag⁺.