2014-Sustainable Industrial Processing Summit
SIPS 2014 Volume 5: Composite, Ceramic, Quasi-crystals, Nanomaterials & Coatings
| Editors: | Kongoli F |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2014 |
| Pages: | 578 pages |
| ISBN: | 978-1-987820-07-2 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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X-ray absorption near edge spectroscopy studies of RCo1-xNixO3 (R = La, Nd)
Vinod Kumar1;1NATIONAL INSTITUTE OF TECHNOLOGY HAMIRPUR, Hamirpur (H.P), India;
Type of Paper: Regular
Id Paper: 295
Topic: 14
Abstract:
The substituted rare earth cobaltites (RCo1-xNixO3) oxide materials have been proven to be good thermoelectric and solid oxide fuel materials. We here report x-ray absorption near edge spectroscopy (XANES) at Co and Ni K-edges of RCo1-xNixO3 (R = La, Nd) along with L3 edges of La/Nd and understand the spectral features related to the electronic structure of these perovskites. The XANES spectra of Co, Ni and La/Nd K-edge confirm the homovalent +3 valence state in all the compositions and exclude the possibility of oxygen non stochiometic type defects and any valence change upon substitution. The existence of pre- edge peak in Co K- edge spectra reflects 1s-3d transition and provides information about the occupancy of 3d orbitals. The pre-edge spectral features which are assigned as eg and t2g, further show strong dependence on Ni concentration and revealed spin state transition of Co ions. These spin state transitions have been explained in terms of crystal field effect and have been found consistent with x-ray diffraction and magnetization studies.