Preparation, structure and luminescence properties of the Ln1-xCaxVO4, Ln= La, Eu (0≤ x≤ 0.2) phases

Abstract

Alkaline-earth metal vanadates are important in various fields, including chemical and biological applications, luminescent devices and optical fibers. Vanadates exhibit unusual magnetic, optical, thermally-activated, and X-ray luminescence properties [1]. They present unique features and alternative technology and photocatalysis have recently attracted considerable attention. The most widely used photocatalyst TiO2 is only active under ultraviolet light irradiation [2, 3]. Europium (EuVO4)[4] and lanthanum (LaVO4)[5] vanadates are of special interest, since they are among the most promising visible-light-driven photocatalysts [6]. These compounds also offer chemical stability and non-toxicity. They have been used in a range of biological applications, such as fluorescent probes for single-molecule tracking, drug development, protein detection and fluorescent bio-labeling [7, 8]. The search for new rare-earth orthovanadates leads to “created” cations, including partial substitution Eu3+/Ca2+ and La3+/Сa2+. The aim of this work was to study the conditions of synthesis of the Ln1-xCaxVO4, Ln= La, Eu (0≤ x≤ 0.2) phases and to investigate their structural features, as well as their morphological and physical properties.