Cover Image

Phase formation processes and synthesis of solid solutions in Ca-R-Nb-M-O systems

A. A. Levina, N. O. Tadevosyan, S. A. Petrova, E. S. Buyanova, M. V. Morozova

Abstract


During the study of the phase formation process in Ca-R-Nb-M-O systems (R=La, Bi, M=Mo, W), an attempt was made to obtain single-phase compounds of CaRNbMO8 composition by the standard ceramic technique. In addition, samples based on LaNbO4, CaWO4, BiNbO4 were also synthesized by the standard ceramic technique. The phase composition of the samples was studied by XRD analysis. The electrical conductivity of the obtained solid solutions and potential composite materials was investigated by impedance spectroscopy.

Keywords


sheelite; fergusonite; solid solutions; electrical conductivity

Full Text:

PDF

References


Goodenough JB. Oxide-Ion Electrolytes. Annu Rev Mater Res. 2003;33:91–128. doi:10.1146/annurev.matsci.33.022802.091651

Fergus JW. Electrolytes for solid oxide fuel cells. J Power Sources. 2006;162(1):30–40. doi:10.1016/j.jpowsour.2006.06.062

Malavasi L, Fisher CAJ, Islam MS. Oxide-ion and proton conducting electrolyte materials for clean energy applications: structural and mechanistic features. Chem Soc Rev. 2010;39: 4370–87. doi:10.1039/B915141A

Orera A, Slater PR. New Chemical Systems for Solid Oxide Fuel Cells. Chem Mater. 2010;22(3):675–90. doi:10.1021/cm902687z

Haugsrud R, Norby T. Proton conduction in rare-earth ortho-niobates and ortho-tantalates. Nat Mater. 2006;5:193-6. doi:10.1038/nmat1591

Cava RJ, Roth RS, Negas T, Parker HS, Minor DB. Crystal Chemistry, Modulated Structure, and Electrical Conductivity in the Oxygen Excess Scheelite-Based Compounds La1-xThxNbO4+x/2 and LaNb1-xWxO4+x/2. J Solid State Chem. 1981;40(3):318–29. doi:10.1016/0022-4596(81)90398-4

Vu TD, Barre M, Adil K, Jouanneaux A, Suard E, Goutenoire F. Investigation of the La2O3–Nb2O5–WO3 ternary phase diagram: Isolation and crystal structure determination of the original La3NbWO10 material. J Solid State Chem. 2015;229:129–34. doi:10.1016/j.jssc.2015.05.022

Deepa M, Rao PP, Sumi S, Radhakrishnan ANP, Koshy P. New Negative Temperature Coefficient Ceramics in Ca–Ce–Nb–M–O (M=Mo or W) System. J Am Ceram Soc. 2010;93(6):1576–9. doi:10.1111/j.1551-2916.2010.03616.x

Li C, Bayliss RD, Skinner SJ. Crystal structure and potential interstitial oxide ion conductivity of LnNbO4 and LnNb0.92W0.08O4.04 (Ln = La, Pr, Nd). Solid State Ionics. 2014;262:530–5. doi:10.1016/j.ssi.2013.12.023




DOI: https://doi.org/10.15826/chimtech.2020.7.1.03

Copyright (c) 2020 Anastasiya A. Levina, Nadezhda O. Tadevosyan, Sofya A. Petrova, Elena S. Buyanova, Mariya V. Morozova

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Scopus logo WorldCat logo DOAJ logo CAS logo BASE logo eLibrary logo

Chimica Techno Acta, 2014-2024
ISSN 2411-1414 (Online)
Copyright Notice