A new metastable phase of needle-like nanocrystalline VO2 • H2O and phase transformation

被引：67

作者：

Gui, Z

Fan, R

Chen, XH ^{[1
]}

Wu, YC

机构：

[1] Univ Sci & Technol China, Struct Res Lab, Hefei 230026, Peoples R China

[2] Univ Sci & Technol China, Dept Chem, Hefei 230026, Peoples R China

[3] Univ Sci & Technol China, Dept Phys, Hefei 230026, Peoples R China

来源：

JOURNAL OF SOLID STATE CHEMISTRY | 2001年 / 157卷 / 02期

基金：

中国国家自然科学基金;

关键词：

novel phase; VO2 center dot H2O; hydrothermal synthesis; phase transformation;

D O I：

10.1006/jssc.2000.9037

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Needle-like nanocrystalline VO2 . H2O, crystallized in a new metastable phase with orthorhombic symmetry (a=6.015, b = 4.642, and c = 3.763 Angstrom), was synthesized by a long hydrothermal reaction from NH4VO3 and hydrazine. The structure and composition of these nanocrystallites were characterized by X-ray powder diffraction, transmission electron microscopy, selected area electron diffraction, infrared absorbency spectroscopy, and thermogravimetric analysis. The influence of chemical reaction conditions on the features of the final products was investigated, and the optimum conditions were found to be 170 degreesC for 15 days with a N2H4 concentration of 8.0%. Differential scanning calorimetry was conducted to study the phase transformation from as-prepared metastable VO2 . H2O to the more stable (B)VO2 and rutile-tvpe VO2. (C) 2001 Academic Press.

引用

页码：250 / 254

页数：5

共 22 条

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