Synthesis And Characterization Of Eu And Tb Codped Oxides Phosphors For White LEDs Application

In this paper, the Eu3+and Tb3+co-doped RE2O3(M=Gd, Y) phosphors have been prepared by the hydrothermal and the solid-phase method. The interaction of the doped ions with different concentration and the luminescent properties of the nanocrystals and microcrystals have been studied systematically. And studied the luminescent properties effected by the relative change of the Eu3+ions and Tb3+ions concentration. The main research orientation and the adoped methods just as follows:1. The homogeneous one-dimensional nanowires of RE2O3:Eu/Tb were prepared by the hydrothermal method. For the Eu3+ions, the intensity of electric dipole transition (5D0�'7F2) is stronger than the intensity of magnetic dipole transition (5D0�'7F1). It means that the luminescence centers were deviating from the inversion center of symmetry, so the odd item of the crystal field had an obvious effect on it.2. For the samples of Y2O3, the luminescent intensity of the samples obtained by hydrothermal method was stronger than the intensity of the samples obtained by solid-phase method. an opposite result was got for the samples of Gd2O3.3. For the samples of Y2O3, there was obvious energy transition from the Eu3+ions to Tb3+ions when Eu3+ions and Tb3+ions co-doped in Y2O3, which means that the Tb3+ions were efficient sensitizer for the Eu3+ions in the Y2O3host. But the absolute intensity was lower than doped only one doped ion. However in the samples of Gd2O3existed energy transition from Tb3+ions to Eu3+ions.4. When Eu3+ions and Tb3+ions co-doped in Y2O3host, both blue-fluorescence from Characteristics light emitting of Tb3+ions and red-fluorescence from Characteristics light emitting of Eu3+ions were observed. And as changing ratio of the Eu3+ions and Tb3+ions the proportion of red and blue intensity changed, too. So via some appropriate adjust hope to achieve white light.5. When Eu3+ions and Tb3+ions co-doped in Y2O3host, as increase the concentration of the doping ions both Eu3+ions and Tb3+ions would increase the intensity of luminescence from Eu3+ions compared to from Tb3+ions. And the effect of Eu3+ions concentration were more obvious on it.