Synthesis, characterization and formation mechanism of metastable phase VO{sub 2}(A) nanorods

Journal Article · Sun Sep 01 00:00:00 EDT 2013 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2013.05.016· OSTI ID:22341782

Cheng, X. H.; Xu, H. F.; Wang, Z. Z.; Zhu, K. R.; Li, G. ^[1]; Jin, Shaowei ^[1]

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1. School of Physics and Materials Science, Anhui University, Hefei 230039 (China)

Graphical abstract: - Highlights: • Pure phases of VO{sub 2}(B) and VO{sub 2}(A) were prepared by a facile hydrothermal method. • Belt-like particles prepared at 180 °C was indexed as monoclinic VO{sub 2}(B) phase. • Rod-like particles prepared at 230 °C was indexed as tetragonal VO{sub 2}(A) phase. • VO{sub 2}(A) nanorods resulted from VO{sub 2}(B) nanobelts by assembly and crystal adjustment. - Abstract: Pure phase VO{sub 2}(A) nanorods were synthesized via the reduction of V{sub 2}O{sub 5} by oxalic acid during the hydrothermal treatment. Two sets of samples were prepared by varying both system temperature and reaction time under a filling ratio of 0.40 for observing the formation and evolution of VO{sub 2}(A) nanorods. Structures were characterized by X-ray diffraction, scanning and transmission electron microscopies, respectively. It was found that VO{sub 2}(B) was firstly formed and then transformed into VO{sub 2}(A) as the increasing system temperature or extending reaction time. An assembling and following crystal adjustment was proposed for explanation the formation process of VO{sub 2}(A) from VO{sub 2}(B). For VO{sub 2}(A) nanorods, the phase transition temperature of 169.7 °C was higher than that of the VO{sub 2}(A) bulk, it might be ascribed to the lower crystallinity or nonstoichiometry in VO{sub 2}(A) nanorods. VO{sub 2} nanostructures with controllable phases and properties should find their promising applications in a single VO{sub 2} nanodevice.

• OSTI ID: 22341782
• Journal Information: Materials Research Bulletin, Vol. 48, Issue 9; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
CRYSTALS
HYDROTHERMAL SYNTHESIS
MONOCLINIC LATTICES
NANOSTRUCTURES
OXALIC ACID
PHASE TRANSFORMATIONS
TRANSITION TEMPERATURE
TRANSMISSION ELECTRON MICROSCOPY
VANADIUM OXIDES
X-RAY DIFFRACTION