One-step rapid hydrothermal synthesis of monoclinic VO2 nanoparticles with high precursors concentration

In this study, monoclinic vanadium dioxide (VO2) nanoparticles were synthesized by one-step rapid hydrothermal treatment of a sol precursor, and the obtained products were examined using various analytical methods. Results indicated that monoclinic VO2 nanoparticles could be obtained using ammonium metavanadate as the precursor at a high concentration of 2.37 M and the shortest duration was only 1 h. X-ray diffraction (XRD) revealed that VO2 presented high crystallinity with a pure monoclinic phase. Phase transition latent heat of VO2 was estimated to be 45.5 J/g. Furthermore, VO2 powders were mostly composed of granules with a size distribution ranging from 20 nm to 100 nm. Monoclinic VO2 nanoparticles were derived from the decomposition of the intermediate (NH4)2V4O9.