Open AccessФазовые превращения и особенности фотолюминесценции твердых растворов Gd-=SUB=-2(1-x)-=/SUB=-Tb-=SUB=-x-=/SUB=-Eu-=SUB=-x-=/SUB=-O-=SUB=-3-=/SUB=-
Author(s) -
В. В. Баковец,
I. P. Dolgovesova,
T. D. Pivovarova,
М. И. Рахманова
Publication year - 2020
Publication title -
fizika tverdogo tela
Language(s) - English
Resource type - Journals
eISSN - 1726-7498
pISSN - 0367-3294
DOI - 10.21883/ftt.2020.12.50219.161
Subject(s) - photoluminescence , monoclinic crystal system , annealing (glass) , crystallinity , materials science , solid solution , crystallography , analytical chemistry (journal) , crystal structure , spectroscopy , activator (genetics) , hydrogen , chemistry , physics , metallurgy , optoelectronics , biochemistry , organic chemistry , chromatography , quantum mechanics , gene
Solid solutions Gd2(1-x)TbxEuxO3, where x = 1 and 2.5 mol%, were obtained in an atmosphere of air and hydrogen by the sol-gel method followed by annealing at 700-1200 °C. It was found by XRD and IR spectroscopy that, during annealing, the solutions undergo chemical and phase transformations of the cubic modification into the monoclinic one and change the degree of crystallinity. Under some annealing conditions, the solid solution contains microinclusions of the Tb7O12:Eu3+ phase, which is not formed in a hydrogen atmosphere or at a high activator concentration of 2.5 mol% at 1200 oC. In accordance with these transformations, a redistribution of the photoluminescence activators Tb3+ and Eu3+ occurs over the centrosymmetric C3i, noncentrosymmetric C2 positions of the crystal lattice, and the surface states of Cs. As a result of these rearrangements, the parameters of the photoluminescence spectra change, which are associated with a change in the ways of transferring the excitation energy of the main radiative transitions of the photoluminescence activators Tb3+ and Eu3+.