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

In this study, monoclinic vanadium dioxide (VO 2 ) 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 VO 2 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 VO 2 presented high crystallinity with a pure monoclinic phase. Phase transition latent heat of VO 2 was estimated to be 45.5 J/g. Furthermore, VO 2 powders were mostly composed of granules with a size distribution ranging from 20 nm to 100 nm. Monoclinic VO 2 nanoparticles were derived from the decomposition of the intermediate (NH 4 ) 2 V 4 O 9 . Monoclinic vanadium dioxide (VO 2 ) nanoparticles can be synthesized by one-step rapid hydrothermal treatment of sol precursor with high concentration. Highlights The monoclinic vanadium dioxide (VO 2 ) nanoparticles can be synthesized by high-temperature hydrothermal method at above 300 °C. The duration of hydrothermal can be shorten to 1 h. The VO 2 nanoparticles could be obtained at a high precursor concentration of 2.37 M. The as-prepared VO 2 samples have high phase transition heat and good phase transition performance.