E. D. Baldin, N. V. Lyskov, V. A. Rassulov, A. V. Shlyakhtina
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引用次数: 0
Abstract
The phase formation of neodymium tungstate Nd2WO6 from mechanically activated oxides was studied in a wide temperature range: 25–1600°C. Conditions for the formation of various polymorphic modifications were determined: low-temperature orthorhombic β-Nd2WO6 and δ-Nd2WO6 (P212121 (no. 19)); high-temperature monoclinic Nd2WO6 (C12/c1 (no. 15)). Optical absorption spectra were studied for polymorphic ceramics with a nominal composition of Nd2WO6. Differences in the spectra of δ-Nd2WO6 and monoclinic Nd2WO6 were detected. Both modifications (δ-Nd2WO6 and monoclinic Nd2WO6) showed proton conductivity with activation energies of 1.05 and 1.06 eV, respectively. For the Ca-containing solid solution with a monoclinic structure (Nd\(_{{1 - x}}\)Cax)2WO\(_{{6-\delta }}\) (x = 0.01), whose overall conductivity increases compared to that of pure monoclinic Nd2WO6, hole conductivity predominates in air.
期刊介绍:
Russian Journal of Physical Chemistry A. Focus on Chemistry (Zhurnal Fizicheskoi Khimii), founded in 1930, offers a comprehensive review of theoretical and experimental research from the Russian Academy of Sciences, leading research and academic centers from Russia and from all over the world.
Articles are devoted to chemical thermodynamics and thermochemistry, biophysical chemistry, photochemistry and magnetochemistry, materials structure, quantum chemistry, physical chemistry of nanomaterials and solutions, surface phenomena and adsorption, and methods and techniques of physicochemical studies.