Tunable Spectrum Of Oxyapatite Of Alkaline-rare Earth Silicate Phosphors

In this thesis, a series of phosphors Me4La6-oxyapatite:Eu(2+,3+)（Me=Ca，Mg，Sr and their combination）series of different valence state of europium ion activationof single matrix light color series phosphor were synthesized by high-temperaturesolid state reactions in weak reduction atmosphere. Through that the singlepermutation and the crystalline structure of the double substitutionthe matrix of asingle alkaline earth metal ions fine-tuning, phosphor spectrum modulation. Using themethod of X-ray powder diffraction (XRD) phase and cell parameters, X-rayphotoelectron spectroscopy (XPS) determine the chemical state of dopants. The roomtemperature and liquid nitrogen temperature spectrum detailed studies to determine theluminescence center of cells for the crystallography and best.Phosphors were pure oxyapatite phase P63/m (176) space group. The latticeparameters a, c with the amount of substitution presents a good linear relationship.The phosphor Eu2+and Eu3+coexist, Eu2+content is inversely proportional to the totalconcentration of dopants. The excitation spectra of sample at room temperature by thef-d transition of Eu2+strong excitation band and two kinds of Eu3+luminescence centercharge transfer transition belt (CTB) and f-f transition series of line. The emissionspectra of phosphor at room temperature under excitation into Eu2+or CTS of Eu3+,the intensities of5D1are much stronger than that of5D0. It is approvable theluminescence is Eu2+sensitizing Eu3+situated in site4f, its light life is longer than5D0level, phosphor in the coexistence of three oxygen vacancy. Liquid nitrogentemperature excitation spectra and emission spectra have not great difference, but highlevel emission is stronger.Alkaline earth metal cations Me=(Ca&Mg),(Mg&Sr),(Ca&Mg&Sr) combined, the total emission of Eu2+and Eu3+, in the study of oxygen radicals apatite phosphor matrix is a new result. Photoluminescence spectra changed with the matrix cations, under ultraviolet radiation, appropriate of phosphor sample at room temperature is closeto white light colors glow. In near ultraviolet chip stimulates the single-component alllight color W-LEDs lights with phosphor has potential application value. Research of this paper enriches the Eu3+spectral characteristics, especially the mixed valence europium doping of relevant results provides useful scientific reference for further research.