Study On The Construction And Luminescent Properties Of Diphenylphosphoric Acid-Mediated High-Nucleus Silver Alkynyl Clusters

High-nucleus alkyne silver clusters have attracted widespread attention due to their diverse structures and excellent physicochemical properties.It is very difficult to prepare high-nucleus silver clusters due to the complexity of the self-assembly process and various complex factors.Previous studies showed that choose the protective silver acetylene as a precursor,by adopting anionic template induction,change anionic template induction,solvent changes,pH,introducting of peripheral regulatory ligands and changing in the types of peripheral counter anions et al,we can synthesis a series of diverse high-nucleus alkyne silver cluster with diverse structures and different properties.Study along with high-nucleus silver clusters development continuously thorough,to control structure and improve performance have become the focus of attention by modifying certain organic ligands containing specific properties and functions on the surface of high-nucleus silver clusters.The study on the peripheral organic ligands,especially oxygen-containing ligands such as organic acids,on the structure and properties of silver alkyne clusters needs further development.In addition,on the basis of the use of vanadate(VO43-)template anions to construct high-nucleus silver alkyne clusters in the early stage of the research group,using a new negative trivalent tetrahedral anion(AsO43-)as a template can further enrich the types of template anions.Using[AgC?CR]n(R=tBu,iPr)as the precursor and Ph2PO2H as the mediate ligand,a series of high-nucleus silver alkynyl clusters were constructed by introducing carbonate/arsenate as templatesThe main research contents of this paper include:1)Construction and characterization of a series of diphenylphosphoric acid-mediated high-nucleus silver alkynyl clusters.Under the mediate of Ph2PO2H,four diphenylphosphoric acid-mediated high-nucleus silver alkynyl clusters were constructed by solvent thermal method by introducing foreign template anions into the solution system of silver alkyne[AgC?CR]n(R=tBu,iPr)/soluble silver salt(Agtfa/AgPF6,tfa=CF3CO2-).X-ray single crystal diffraction analysis,(SXRD)reveal its formula is respectively[(C?CtBu)15(tfa)3(Ph2PO2)2I]((CO3)2@Ag25)?[(AsO4)@Ag20(C ? CtBu)8(Ph2PO2)7(CF3CO2)2(CH3CN)]((AsO4)@Ag20)?[(AsO4)@Ag22(Ph2PO2)7(C?CtBu)10(CH3OH)(H2O)2(PF6)2]((AsO4)@Ag22)?[(AsO4)@Ag21(C?CiPr)8(Ph2PO2)8(tfa)2·DMF·5CH3CN·2H2O·Cl]((AsO4)@Ag21).Among them,the CO32-of cluster(CO3)2@Ag25 is from carbon dioxide in air.The clusters(AsO4)@Ag2O,(AsO4)@Ag20 and(AsO4)@Ag22 are three cases of high-core silver clusters with similar cage structure using arsenate as template.The the molecular composition and structure of clusters were further confirmed by FT-IR,UV-visible,X-ray powder diffraction(PXRD)and NMR,which laid a good foundation for further study on the correlation between structure and properties.The successful construction and structural characterization of related clusters prove that diphenylphosphoric acid is a feasible ligand for modification on the surface of silver clusters,which reveals a variety of coordination patterns between diphenylphosphoric acid and silver clusters.Meawhile,the use of new template anions in the construction of high-nucleus silver alkyne clusters further enriched the types of template anions..2)The thermal stability and light absorption performance of a serious of diphenylphosphoric acid-mediated high-nucleus silver alkynyl clusters were characterized by thermal analysis(TGA)and Solid-state UV.Thermal analysis shows that the initial thermal decomposition temperature of clusters(CO3)2@Ag25?(AsO4)@Ag20?(AsO4)@Ag22 are 213??310??316?,which shows that the clusters have good thermal stability.Solid-state UV showed that energy gaps of the clusrers(CO3)2@Ag25?(AsO4)@Ag20?(AsO4)@Ag22 are 2.58 eV,2.54 eV and 2.67 eV,respectively,which shows the introduction of different template anions can significantly chang the energy gap of the clusters.3)The fluorescence properties of a serious of diphenylphosphoric acid-mediated high-nucleus silver alkynyl clusters were investigated by fluorescence spectroscopy(PL).Fluorescence spectrum shows that the cluster(CO3)2@Ag25 emits orange-red light at 77 K,the cluster(AsO4)@Ag20 and(AsO4)@Ag22 emit white light,which all show good photoluminescence and are the potential materials for low temperature fluorescent applications.The results show that the cluster(CO3)2@Ag25 emits orange-red light at 77 K,The emission maxima are placed in wavelength of 557 nm.The cluster(AsO4)@Ag20 and(AsO4)@Ag22 emit white light and orange-red light at 77 K,respectively.The emission maxima are placed in wavelengths of 506 and 598 nm.They are a series of potential low-temperature fluorescent materials.