6533b859fe1ef96bd12b8156

RESEARCH PRODUCT

Spectroscopic study of the electric field induced valence change of Fe-defect centers in SrTiO(3)

Alexei KuzminKristof SzotKristof SzotRainer WaserRainer WaserDzintars BerzinsRegina DittmannAleksandr KalinkoJuris PuransChristian Lenser

subject

010302 applied physicsValence (chemistry)Absorption spectroscopyExtended X-ray absorption fine structureChemistryAb initioGeneral Physics and Astronomy02 engineering and technology021001 nanoscience & nanotechnology01 natural sciencesXANESlaw.inventionJsymbols.namesakeCrystallographyOxidation statelaw0103 physical sciencesddc:540symbolsPhysical and Theoretical Chemistry0210 nano-technologyElectron paramagnetic resonanceRaman spectroscopy

description

The electrochemical changes induced by an electric field in Fe-doped SrTiO(3) have been investigated by X-ray absorption spectroscopy (XANES and EXAFS), electron paramagnetic resonance (EPR) and Raman spectroscopy. A detailed study of the Fe dopant in the regions around the anode and cathode reveals new insights into the local structure and valence state of Fe in SrTiO(3) single crystals. The ab initio full multiple-scattering XANES calculations give an evidence of the oxygen vacancy presence in the first coordination shell of iron. Differences in the length and disorder of the Fe-O bonds as extracted from EXAFS are correlated to the unequivocal identification of the defect type by complementary spectroscopical techniques to identify the valence state of the Fe-dopant and the presence of the Fe - V(Ö) complexes. Through this combinatorial approach, novel structural information on Fe - V(Ö) complexes is provided by X-ray absorption spectroscopy, and the relation of Fe-O bond length, doping level and oxidation state in SrTi(1-x)Fe(x)O(3) is briefly discussed.

yearjournalcountryeditionlanguage
2011-10-18
10.1039/c1cp21973ahttps://hdl.handle.net/2128/7352