Preparation Of 3D Organic Skeletons Based On Copper(Ⅰ) Cluster Complexes And Their Fluorescence Properties

The unusual photophysical characteristics of coin metal complexes with a d10 electronic structure are gaining growing interest due to their structural variety.The absence of the d-d excited state enables nonradiative deactivation of the excited state to the ground state.Copper is a plentiful and affordable resource,and Cu(Ⅰ)complexes provide a viable alternative to noble metal-based luminous compounds from the standpoint of effective exploitation of common metals.In view of these advantages,the strongly emitting Cu(Ⅰ)complexes were prepared by modifying them accordingly to address the disadvantages of large particle size and poor luminescence performance.Therefore,three distinct Cu(Ⅰ)complexes were produced as follows in this thesis.(1)By solvent volatilization,novel Cu4I4(Gly)4 blue-violet luminous compounds based on metal-ligand charge transfer(MLCT)jump were produced.Using Fourier infrared spectroscopy(FT-IR),X-ray diffraction spectroscopy(XRD),scanning electron microscopy analysis(SEM),X-ray electron spectroscopy(XPS),ultraviolet-visible diffuse reflectance spectroscopy(Uv-vis DRS),and fluorescence spectroscopy,the crystal structures and luminescent properties of luminescent complexes were investigated.The results demonstrated that the luminous compounds formed from clusters of copper iodide and glycine had a tetragonal crystal structure with a space group of F43m.At 397 nm photoexcitation,the d-d energy level jump of Cu(Ⅰ)produced by Cu4I4(Gly)4 luminescent complexes released the most intense blue-violet light at 423 nm.The coordination of glycine with the copper iodide cluster luminous center boosted the luminescence intensity.when the temperature was increased from 298 K to 398 K,the fluorescence intensity stayed at 60.17 percent of the initial luminescence intensity.The luminescent compound had a fluorescence decay lifespan of 517 ns,and its chromaticity coordinates(0.1577,0.0318)were placed in the blue-violet region with a 92%color purity.(2)Using the solvent volatilization approach,Cu3I4(Gly)3/Ag,a metalorganic backbone comprising iodine-copper clusters modified by silver hybridization,was synthesized.Using FT-IR,XRD,SEM,XPS,Uv-vis DRS,and fluorescence spectroscopy,the crystal structure and luminescence characteristics of luminous compounds were analyzed.The results demonstrate that the luminous compounds formed by introducing silver to produce vacancies in Cu(Ⅰ)iodide clusters and glycine have a tetragonal crystal structure.The introduction of Ag(Ⅰ)permits the transfer of Cu(Ⅰ)excitons to Ag(Ⅰ)to form Ag generating vacancy defects and providing vacancies,thereby increasing the number of defective luminescent centers and enhancing the luminescence quantum efficiency.In contrast,excess defects induce non-radiative complexes of luminescent excitons as well as the formation of more positively charged excitons.Copper ions are shielded by glycine coordination,which increases the luminescence efficacy of the complexes.When the temperature was elevated from 298 K to 403 K,the fluorescence intensity of Cu3I4(Gly)3/Ag retained 68.56%of its original luminescence intensity,and its quantum efficiency was 1.95%,demonstrating outstanding luminescent performance and strong thermal stability.(3)Ti3C2Tx MXene was successfully prepared by HF exfoliation of Ti3AlC2 MXA,followed by the preparation of organic-inorganic hybrid composite orange-red fluorescent materials with different mass fractions of MXene doped with Cu3I4(Gly)3/Ag by solvent volatilization method,with Cu3I4(Gly)3/Ag forming crystals on the surface of MXene and producing Schottky heterostructures MXene doped Cu3I4(Gly)3/Ag/MXene emits orange-red light at 654 nm,which is obtained from the luminescence of Cu3I4(Gly)3/Ag crystals,in contrast to the undoped MXene halogenated Cu-Ag-Ag heterostructure,which lowers reverse tunneling of the current.The best luminescence performance of Cu3I4(Gly)3/Ag/MXene was achieved at 0.6 wt%MXene doping,with a minimum activation energy difference of 0.2948 eV,a broadening of the UV absorption range by approximately 4 nm,an enhanced effect of temperature on photochromism,a 24%decrease in fluorescence lifetime,and a 136%increase in quantum efficiency.