Investigation of the Heterovalent Substitution Cadmium for Lanthanum in Molybdate La[sub.2]MoO[sub.6]

• Published in: Journal of chemistry 2021-05, Vol.2021
• Main Authors: Chebyshev, K. A, Ignatov, A. V, Pasechnik, L. V, Selikova, N. I, Get`man, E. I
• Format: Article
• Language: English
• Subjects: Cadmium; Diffraction; Fluorine compounds; Infrared spectroscopy; Investigations; Lanthanum; X-ray spectroscopy; X-rays
• ISSN: 2090-9063
• DOI: 10.1155/2021/5537048

This paper presents the investigation of the heterovalent substitution of cadmium for lanthanum in the La[sub.2-x]Cd[sub.x]MoO[sub.6-x/2] system. The samples were synthesized by the solid state reaction method at 1000°C. The samples were characterized by X-ray powder diffraction with Rietveld refinements, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy methods. The study results revealed that cadmium incorporation in the lanthanum molybdate leads to the transformation of the tetragonal structure of La[sub.2]MoO[sub.6] to a cubic fluorite-like one. The content of the cubic phase reaches 94% in the Lа[sub.1.4]Cd[sub.0.6]MoO[sub.5.7] sample. The unit cell parameter of fluorite-like-phase decreases with cadmium content rising. The preferred location of cadmium ions in the cubic structure was established by the Rietveld refinement method. The heterovalent substitution cadmium for lanthanide in tetragonal La[sub.2]MoO[sub.6] molybdate leads to the cubic fluorite phase stabilization in a similar way as it occurs in the process of reduction.