Investigation of structural and optical properties of CaTiO3 powders doped with Mg2+ and Eu3+ ions

Abstract

In this work, CaTiO3 powders doped with Mg2+ ions and CaTiO3 powders co-doped with Mg2+ and Eu3+ ions were prepared by the polymeric precursor method (PPM). These powders were characterized by different characterization techniques to study the influence of Mg2+ doping as well as Mg2+ and Eu3+ codoping in structural and optical properties of CaTiO3 perovskite-type structure. The Rietveld refinement and Micro-Raman analyses suggested the substitution Mg2+ and Eu3+ ions in the A-site of CaTiO3 perovskite. The influence of Mg2+ doping can be detected by the displacement of calcium and oxygen atomic positions when compared to the non-doped CaTiO3 powder. When Eu3+ ions are added to the Asite of this perovskite the excess of positive charge can be compensated by the formation of calcium vacancies. Luminescence data showed that Ca1-xMgxTiO3 and Ca1xMgx/2Eu2y/3TiO3 powders are potential materials for fabrication of lighting devices based on near-UV and blue LED using an excitation wavelength of 397 and/or 450 nm. (C) 2015 Elsevier B.V. All rights reserved.