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Indexed by:Journal Papers

Date of Publication:2015-06-01

Journal:MATERIALS RESEARCH INNOVATIONS

Included Journals:EI、SCIE、Scopus

Volume:19

Issue:4

Page Number:295-302

ISSN No.:1432-8917

Key Words:VO2 polymorphs; VO2(A); VO2(M); Hydrothermal treatment; Phase transition; Optical properties

Abstract:In this paper, the conversion of VO2(B) nanobelts under the hydrothermal condition in the absence/presence of dopant was studied. The synthetic conditions, such as the reaction temperature, reaction time, quantity of the dopants and kinds of dopants, were briefly discussed to prepare VO2(A) and W doped VO2(M) solid solution. It was found that the dopant played a crucial role in controlling VO2 polymorph, and the results showed that VO2(A) was obtained in the absence of dopant, whereas W doped VO2(M) was obtained in the presence of tungstenic acid. The transformation mechanism from VO2(B) to VO2(A) and W doped VO2(M) was discussed in detail. The phase transition temperature (Tc) of VO2(A) and W doped VO2(M) was evaluated by differential scanning calorimetry. It is found that doped atoms can be successfully doped into the crystal lattice of VO2(M) matrix, and the Tc of W doped VO2(M) can be reduced by W doping. The optical switching properties were studied by the variable temperature infrared spectra, and it was found that the as obtained VO2(A) and W doped VO2(M) had outstanding thermochromic characters and optical switching properties.