Gram-scale Preparation Of Stable Hydride M@Cu₂₄(M=An,Cu) Nanoclusters

In recent years,copper-hydrogen nanoclusters(Cu H NCs)have become a research hotspot due to their low cost and easy availability,excellent hydrogen storage capacity and catalytic performance.However,because copper is easily oxidized by air,the preparation of copper nanoclusters generally needs to be carried out in a harsh environment;at the same time,nanoclusters are extremely unstable,difficult to store in the air,and the yield is extremely low,which leads to their It is difficult to crystallize.Based on this,we proposed two strategies to improve the stability of copper-based nanoclusters,laying a material foundation for the subsequent exploration of the properties of copper clusters.In addition,we also realized the modification of single atoms on the surface of gold-copper alloy nanoclusters by means of high-temperature heating.The main research contents of this paper include:1.In this study,we achieved the preparation of Cu H NCs under environmental conditions through two different methods:(1)metal doping method;(2)ligand modification method.Both methods significantly improve the antioxidant capacity of the clusters,thereby significantly improving their stability.Specifically,in this paper,three copper-rich nanoclusters were controllably synthesized by a one-pot method in a natural environment:Au Cu₂₄H₂₂(PPh₃)₁₂,Cu₂₅H₂₂((p-FPh)₃P)₁₂ and Au Cu₂₄H₂₂((p-FPh)₃P)₁₂,and then we use a variety of testing methods to characterize their structure and composition.We have proved their stability through time-dependent ultraviolet-visible spectroscopy;more importantly,we have realized the mass preparation of M@Cu₂₄(M=Cu,Au)NCs protected by ligands with electron-withdrawing groups,which further proves Their superior stability laid an experimental foundation for the subsequent study of the properties of copper-hydrogen nanoclusters.This work is expected to provide important insights for the subsequent large-scale synthesis of ultra-stable copper-based nanomaterials.2.The modification of a single metal atom on the surface of metal nanoclusters has always been a difficult problem.In this work,we first synthesized a novel structure of alloy nanoclusters by a one-pot method:Au_xCu_15-x(DPPMH)₃(SPh Cl₂)₉;then we directly heated it in a toluene solution to transform it into Au_xCu_16-x(DPPMH)₂(DPPM)(SPh Cl₂)₉ nanocluster with a gold atom added to the surface motif.We verified the composition and structure of(Au Cu)₁₅ and(Au Cu)₁₆ through a series of methods such as X-ray single crystal diffraction,mass spectrometry and X-ray photoelectron spectroscopy.This discovery not only provides us with a new method for synthesizing alloy nanoclusters,but also realizes the doping of a single metal atom on the surface for the first time,laying a foundation for the future study of the effect of a single atom on the properties of the cluster.