Syntheis, Structure, Rare Earth Doped Luminescence Properties Of Alkali Earth-rare Earth Complex Fluride Matrix Based On M_1-xR_xF_2+x（M=Ca, Sr, Ba; R=Y, La,Gd）

Fluoride materials represented by fluorite (CaF2) possess many advantages, suchas low phonon energy, wide transmittance light range, which can act as excellentluminescent host materials. Fluoride materials have been widely used in the fields ofluminescence, display, laser and photoelectron devices. Based on the previous studyon the crystal structure and luminescence property of CaF2, a series of novel alkaliearth-rare earth complex fluoride materials, M1-xRxF2+x (M=Ca, Sr, Ba; R=Y, La, Gd)have been devolped in this dissertation. Various preparation methods have beenadopted to synthesize the designed fluoride materials and the optimum experimentalconditions have been determined. The relationships between the phase component,crystal structure, microstructure and the luminescence properties have beeninvestigated, and a series of E3+-doped and Yb3+/Er3+codoped alkali earth-rare earthcomplex fluoride luminescence materials with controlled morphology and excellentluminescence properties have been obtained. The relation of the host compositions,crystal structure, and preparation method with the luminescence properties has beendiscussed in detail. Two kinds of calcium-based rare earth complex fluoride materials,Ca0.65La0.35F2.35and CaY4F14have been studied, and their corresponding preparationtechniques have been optimized. Eu3+-doped and Yb3+/Er3+codoped luminescenceproperties in Cao.65Lao.35F2.35and CaY4F14hosts have been investigated, and theintrinsic luminescence mechanism has been given. Two different preparation methods, the traditional solid-state method and thehydrothermal method, have been comparatively investigated to prepare four kinds ofstronium-based rare earth complex fluoride materials, Sr0.69La0.31F2.31, Sr2LaF7,Sr2YF7and Sr2GdF7. The preparation techniques have been optimized, andEu3+-doped and Yb3+/Er3+codoped luminescence properties and the luminescencemechanism have been investigated. The solid-state method and the hydrothermal method have been comparativelyinvestigated to prepare three kinds of barium-based rare earth complex fluoridematerials, Ba2LaF7, BaYF5and BaGdF5. The optimum preparation techniques andEu3+-doped and Yb3+/Er3+codoped luminescence properties and the luminescencemechanism have been investigated, respectively. The effect of crystal structure, size of the unit cell and the chemical compositionon luminescence properties of Eu3+-doped and Yb3+/Er3+codoped alkali earth-rareearth complex fluoride materials, M1-xRxF2+x (M=Ca, Sr, Ba; R=Y, La, Gd) have beensystematically analyzed. The affecting rule of the symmetry of the crystal structure,crystal field effect and the chemical composition on the luminescence properties havebeen pointed out based on some comparative investigations.