Spectral Properties Of Rare Earth Doped SGG Powders

Rare earth ions have rich energy level transitions,and the rare earth ions doped luminescent materials have been used in many fields such as solid state lighting,medical imaging,agriculture and so on.Eu3+ is a commonly used activator ion in the preparation of red light-emitting materials.It has been widely used in the field of solid state lighting and CRT.Dy3+ is the main activator ion of yellow and white light-emitting materials,and it is also widely used in the field of long afterglow materials.Strontium gallogermanate Sr3Ga2Ge4O14(SGG)crystal which can be used as high temperature pressure piezoelectric material and laser host material owns high melting point and good structural stability.In this paper,SGG was choosed as a matrix material and Eu3+Bi3+,Dy3+ were also choosed as activator ions.Eu3+,Bi3+ and Dy3+ ions doped Sr3Ga2Ge4O14 were prepared by high temperature solid state sintering.The crystal structure and luminescence properties of the samples were characterized by XRD and fluorescence spectroscopy.In the third chapter,the structure and spectral properties of Eu3+ and Bi3+ doped SGG crystals were mainly introduced to investigate the effect of Eu3+ doped concentration of SGG matrix crystallographic structure and spectral properties.The results showed that Eu3+ could form a stable solid solution with the "disordered" structure.The results of emission spectra showed that the main emission peak of Eu3+ doped SGG material was 618nm,when the doping concentration of Eu3+ was up to 15mol%,the luminescence properties of the material could improve the luminescence intensity to the maximum extent.Bi3+ and Eu3+ co-doped results showed that a certain amount of Bi3+ could sensitize the luminescence properties of Eu3+ through the energy transfer from Bi3+ to Eu3+.In the fourth chapter,the structure and spectral properties of Dy3+ and M+(M+=Li+,Na+,K+)doped SGG powder were mainly introduced.The XRD results indicated that Dy3+maximum doping concentration could be 6mol%.When the doping concentration of Dy3+ was 6mol%,the luminescence intensity of the material reached the optimal value.The concentration quenching mechanism of Dy3+ in 571nm emission was the electric dipole-dipole interaction.The research results of charge compenstation M+ showed that M+ could improve the luminescence properties of Dy3+ in varying degrees,Li+ was the most efficient ions which could improve the inteisity of 4F9/2?6H3/2 transition best among all of the M+ions.