Local Structure of Fe Impurity Atoms in ZnO: Bulk versus Surface

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• 作者：J. A. McLeod ; D. W. Boukhvalov ; D. A. Zatsepin ; R. J. Green ; B. Leedahl ; L. Cui ; E. Z. Kurmaev ; I. S. Zhidkov ; L. D. Finkelstein ; N. V. Gavrilov ; S. O. Cholakh ; A. Moewes
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：March 13, 2014
• 年：2014
• 卷：118
• 期：10
• 页码：5336-5345
• 全文大小：452K
• 年卷期：v.118,no.10(March 13, 2014)
• ISSN：1932-7455

文摘

By studying Fe-doped ZnO pellets and thin films with various X-ray spectroscopic techniques, and complementing this with density functional theory calculations, we find that Fe-doping in bulk ZnO induces isovalent (and isostructural) cation substitution (Fe²⁺ 鈫?Zn²⁺). In contrast to this, Fe-doping near the surface produces both isovalent and heterovalent substitution (Fe³⁺ 鈫?Zn²⁺). The calculations performed herein suggest that the most likely defect structure is the single or double substitution of Zn with Fe, although, if additional oxygen is available, then Fe substitution with interstitial oxygen is even more energetically favorable. Furthermore, it is found that ferromagnetic states are energetically unfavorable, and ferromagnetic ordering is likely to be realized only through the formation of a secondary phase (i.e., ZnFe₂O₄), or codoping with Cu.