کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1329577 | 978918 | 2009 | 6 صفحه PDF | دانلود رایگان |

The actual oxygen environment of the tungsten dopant in the Ba2In2−xWxO5+3x/2 solid solution was revealed by combining X-ray absorption spectroscopy at the tungsten LI and LIII edges and at the indium LI edge. Whatever the substitution ratio, the tungsten atoms exhibit a regular octahedral environment. When the substitution ratio increases, the oxygen vacancies are progressively filled until their total occupancy for x=2/3. For x⩾0.3, the perovskite structure is stabilised; the tungsten atoms are randomly distributed in the structure. Although X-ray diffraction revealed a cubic symmetry for these compositions, a local distortion of the indium environment is observed when a tungsten atom is in its surrounding.
Evolution of the XANES signal of Ba2In2−xWxO5+x type compounds with x=0.1 (orthorhombic), x=2/3 (cubic) and of BaWO4, Bi2WO6 and WO3 references, in which tungsten has, respectively, a tetrahedral, distorted octahedral and quasi-regular octahedral environment.Text3Figure optionsDownload as PowerPoint slide
Journal: Journal of Solid State Chemistry - Volume 182, Issue 2, February 2009, Pages 289–294