Studies On The Energy Transfer And VUV Excited Luminescent Properties Of Pr³⁺, Dy³⁺ Or Tb³⁺ Doped Compounds Containing Gadolinium

Vacuum-ultraviolet (VUV) phosphors doped with rare earths become a research focus for their expected applications in mercury-free fluorescent lamps, high-efficient plasma display panels, and fast scintillators.In rescent years, the development and improvement of experimental VUV synchrotron radiation laid the foundation for the study of the high excited states of rare earths. Studies on VUV fluorescent materials focus on more practical in the development of VUV phosphors and extending the state properties of rare earth ions. The VUV fluorescent materials can not only guide the practical applications, but also develop and improve the theory of energy levels of the rare earth ions.This thesis is divived into the following sections:1. The properties of the host absorption band in the VUV range and the absorption band of the 4f-5d transition of Pr3+ and Dy3+ ions doped in NaGdF4 and GdB3O6 are studied. The results showed that 4f-5d absorption band of Pr3+ ion was in the range between 160 nm and 200 nm in NaGdF4 and between 175 nm and 220 nm in GdB3O6; the 4f-5d absorption band of Dy3+ ion was in the range between 130 nm and 170 nm in NaGdF4 and between 155 nm and 185 nm in GdB3O6.2. The properties of the host absorption band in the range of VUV and the absorption of the Tb3+ ion's 4f-5d transition are studied,which of Pr3+ and Tb3+ doped NaGdF4 and GdB3O6.The results showed that Tb3+ ion's 4f-5d absorption band was in the range between 150 nm-200 nm in NaGdF4 and between 170 nm-220 nm in GdB3O6.3. The mechanism of Pr3+ sensitized Gd3+,the energy transfer between Gd3+ and Dy3+ or Tb3+ was studied in NaGdF4 and GdB3O6.The results showed Pr3+ could sensitized Gd3+ efficiently,and put almost all of its energy transfer to Gd3+;While Gd3+ could thansfer most of its energy to Dy3+ and Tb3+,so that Dy3+ emitted 474 nm and 575 nm light,and Tb3+ emitted several peaks with the main peak of 542 nm by downward transition from 5D3 and 5D4 states.