Low-Cost and Facile Synthesis of the Vanadium Oxides VO, VO, and VO and Their Magnetic, Thermochromic and Electrochromic Properties.

In this study, vanadium sesquioxide (VO), dioxide (VO), and pentoxide (VO) were all synthesized from a single polyol route through the precipitation of an intermediate precursor: vanadium ethylene glycolate (VEG). Various annealing treatments of the VEG precursor, under controlled atmosphere and temperature, led to the successful synthesis of the three pure oxides, with sub-micrometer crystallite size. To the best of our knowledge, the synthesis of the three oxides VO, VO, and VO from a single polyol batch has never been reported in the literature. In a second part of the study, the potentialities brought about by the successful preparation of sub-micrometer VO, VO, and VO are illustrated by the characterization of the electrochromic properties of VO films, a discussion about the metal to insulator transition of VO on the basis of in situ measurements versus temperature of its electrical and optical properties, and the characterization of the magnetic transition of VO powder from SQUID measurements. For the latter compound, the influence of the crystallite size on the magnetic properties is discussed.