X-ray powder diffraction study of monoclinic V4+-ZrO2 solid solutions obtained from gels

Rietveld refinement of six monoclinic VxZr1-xO2 solid solutions, with x = 0, 0.01, 0.02, 0.05, 0.075 and 0.1, prepared by heating dried gel precursors at 1300degreesC in air atmosphere, has been characterized using X-ray powder diffractometer data. The present results confirm that crystal structure of these solid solutions contain V4+(Zr4+) cations surrounded by seven oxygens, four at a distance between 2.13 and 2.28 Angstrom (referred as to O(2) in the tetrahedrally coordinated oxygens) and other three at a distance between 2.03 and 2.20 Angstrom (denoted as O(1) in the triangularly coordinated oxygens). The trends in the lattice parameter variation of VxZr1-xO2 solid solutions specimens with the nominal vanadium amount are in accordance with previous results obtained by experiments measured using an internal standard. (C) 2003 Elsevier Science (USA). All rights reserved.