Synthesis and Luminescent Properties of Bismuth Titanates Bi1.6HoxTi2O7 – δ and Bi1.6Mg0.1HoxTi2O7 – δ

Abstract

Pyrochlores Bi_1.6Ho_xTi₂O_7 – δ and Bi_1.6Mg_0.1Ho _xTi₂O_7 – δ, where x = 0, 0.01, 0.05, and 0.1, and Bi_1.5Ho_xTi₂O_7 – δ, where x = 0.25 and 0.5, have been synthesized and their structural, optical, and luminescence properties have been studied. As a result of analyzing the data obtained experimentally and the available theoretical data, it is shown that the intrinsic luminescence of the samples is due to the O2p ↔ Bi6p and Bi6s ↔ Bi6p electron transitions and the impurity luminescence is due to the f–f transitions in Ho³⁺ and the O2p → Ho³⁺ charge transfer.