Sol-gel synthesis of triclinic CoV2O6 polycrystals

• Published in: Ceramics international 2018-11, Vol.44 (16), p.19397-19401
• Main Authors: von Dreifus, Driele, Pereira, Rodrigo, Rodrigues, Ariano D., Pereira, Ernesto C., de Oliveira, Adilson J.A.
• Format: Article
• Language: English
• Subjects: γ-CoV2O6 crystalline structure; γ-CoV2O6 magnetic properties; γ-CoV2O6 polycrystals; γ-CoV2O6 synthesis; γ-CoV2O6 vibrational modes
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2018.07.171

In this paper, a new chemical route synthesis for γ-CoV2O6 is proposed. Based on the CoO-V2O5 phase diagram a study of temperature and calcination times for pure γ-CoV2O6 obtainment is described. X-ray diffraction and Raman spectroscopy experiments revealed the triclinic crystals structure belonging to P-1 spatial group. FEG-SEM images showed that the resulting grains present elongated shape. Rietveld analysis revealed a crystalline anisotropy with preferential crystallographic orientation in the [2 0 − 1] and [1 3 0] planes. The calculated mean crystallite size evidences that the crystallite dimensions are significantly different in the parallel and perpendicular directions. The magnetic properties measurements evidenced an antiferromagnetic transition at 7 K and a detailed view of the magnetization isotherms confirmed a noticeable step-like behavior below TN, characteristic of field-induced transitions.