Isomorphous Substitutions in Luminescent Materials Based on ScVO4

• Published in: Key engineering materials Vol. 865; pp. 37 - 42
• Main Authors: Ardanova, Lyudmyla I., Get'man, Evgeni I., Ignatov, Aleksey V., Radio, Serhii V., Hill, Ian M.
• Format: Journal Article
• Language: English
• Published: Zurich Trans Tech Publications Ltd 30.09.2020
• Subjects: Decomposition; Energy theory; Interaction parameters; Mathematical analysis; Miscibility; Phase stability; Rare earth elements; Solid solutions; Stability analysis; Substitutes; Zircon; Isomorphous Substitution; Solid Solution; Orthovanadate; Rare-Earth Element
• ISSN: 1013-9826; 1662-9795; 1662-9795
• DOI: 10.4028/www.scientific.net/KEM.865.37

The aim of the paper is to define the limits of substitution and phase stability for solidsolutions of orthovanadates with zircon structure Sc1–xLnxVO4, where Ln is a rare-earth element(REE), Ln = Ce – Lu. The mixing energies (interaction parameters) and critical decompositiontemperatures of Sc1–xLnxVO4 solid solutions with the zircon structure were calculated using thecrystal-energy theory of isomorphous miscibility. Diagram of thermodynamic stability visualizingthe substitution limits (x) by the decomposition temperature or the decomposition temperature bythe substitution limits, the dependencies of the decomposition temperatures on the REE atomicnumbers is presented. This diagram also allows assessing areas of stability, instability, andmetastability for Sc1–xLnxVO4 solid solutions. Results of calculations were compared with literaturedata on thermodynamic stability of solid solutions and on substitution limits. The results of thisstudy can be used in the development of new luminescent materials based on ScVO4 modified withREE, in the selection of REE for matrix and activator, in defining optimal proportions of REE inSc1–xLnxVO4 matrices.