Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich, Germany.
Phys Chem Chem Phys. 2011 Dec 14;13(46):20779-86. doi: 10.1039/c1cp21973a. Epub 2011 Oct 14.
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.
采用 X 射线吸收光谱（XANES 和 EXAFS）、电子顺磁共振（EPR）和拉曼光谱研究了电场诱导的掺铁 SrTiO3 中的电化学变化。对阳极和阴极附近区域的 Fe 掺杂剂进行了详细研究，深入了解了 SrTiO3 单晶中 Fe 的局部结构和价态。从头算全多重散射 XANES 计算为铁的第一配体壳层中存在氧空位提供了证据。从 EXAFS 中提取的 Fe-O 键的长度和无序性的差异与通过互补光谱技术来确定 Fe 掺杂剂的价态和 Fe-V(Ö)复合物的存在来明确识别缺陷类型相关。通过这种组合方法，X 射线吸收光谱提供了关于 Fe-V(Ö)复合物的新结构信息，并简要讨论了 SrTi(1-x)Fe(x)O(3) 中 Fe-O 键长度、掺杂水平和氧化态之间的关系。
