Synthesis And Property Investigation Of Ternary Compounds Of AgI+KI System And Ordered Mesoporous Silica

This thesis covers two areas, one is synthesis and property investigation of two compounds of AgI+KI system. The other is the synthesis method of ordered mesoporous silica and its photoluminescence in the ultraviolet range.KAg4I5 and K2AgI3 were prepared by solid reaction method. The ionic conductivities of AgI, KAg4I5 and AgI-KAg4I5 were investigated by complex impedance spectroscopy. It was found that the ionic conductivity of AgI-KAg4I5 is higher than single-phase AgI or KAg4I5 at 150-230?C range, because there was a great deal of interface between AgI and KAg4I5, high-density defects will be created, and those incompact structure could provide lots of transmission-channels for Ag+. The optical properties of K2AgI3 were investigated by photoluminescence (PL) spectra, an photoluminescence emission band at 2.25 eV was found, it was possible in relation to the exciton and a undetermined defect band of K2AgI3.The ordered mesoporous silica SBA-15 was synthesized by hydrothermal method, and its structure was carefully investigated. Photoluminescence in 3.8eV was found in SBA-15. Such emission was shown to be strengthened when aged in the air. Such emission has been carefully investigated by annealing the materials in different temperature and EPR experiment. The 3.8 eV band is suggested to be attributed to the surface silanols generated from ODC(II) and the interstitial water molecules.