ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Convergent-beam electron diffraction has been used to determine the space groups of β- and γ-Zn3(VO4)2 particles in vanadium oxide-doped zinc oxide varistors. The crystal structure of β-Zn3(VO4)2 has been determined to be monoclinic with space group P21 and lattice parameters of a= 9.80 Å, b= 8.34 Å, c= 10.27 Å, and β= 115.8°, whereas that of γ-Zn3(VO4)2 is monoclinic with space group Cm and a= 10.40 Å, b= 8.59 Å, c= 9.44 Å, and β= 98.8°. Energy-dispersive X-ray microanalysis of these two phases shows significant deviations from their expected stoichiometry. It is apparent that the β-phase is, in fact, the metastable Zn4V2O9 phase, whereas the γ-phase either is a new oxide that consists of zinc, vanadium, and manganese or, more likely, is a zinc vanadate phase with a Zn:V atomic ratio of 1:1 that has the ability to go into solid solution with manganese.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1151-2916.2001.tb00673.x
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