INTERACTION MECHANISM OF ENERGY TRANSFER FROM Ce TO Tb IONS IN SILICA AND LaF3

  • Ngô Văn Tâm

Tóm tắt

The phenomenon of energy transfer plays an important role in the development of luminescent materials, especially materials used for manufacturing white LED.The process of luminescence at wavelength 542nm from Tb3+ doped in silica or LaF3 can be stimulated by ultraviolet light near 227 nm. However, the excitation wavelength can be shifted to a more accessible value of 325 nm by co- doping Tb3+ with Ce3+ ions. At this wavelength Ce3+ ions absorb and then transfer the energy to the Tb3+ ions. This process involves the stimulation of the donor followed by energy transfer to acceptor excitation radiation. System co-doped samples Ce, Tb in Silica is made sol-gel method, system co-doped sample ions Ce, Tb in LaF3 is made by hydrothermal method. After surveying the excitation spectrum, fluorescence, measured lifetimes empirical, applied theory Forster, Dexter and computational models of Inokuti and Hirayama or approximate Reisfelds. We determined the mechanism of energy transfer from Ce to Tb in Silica and in LaF3    
điểm /   đánh giá
Phát hành ngày
2019-06-21