Abstract
Amorphous titania thin films with increasing Fe content have been prepared by RF magnetron sputtering. X-ray absorption spectroscopy revealed modifications of both local structures/environment of the Ti and Fe atoms, with formation of phases containing amorphous material and a magnetite-like phase. The temperature dependence of the electrical conductivity of the films was investigated for temperatures higher than half of the Debye temperature (T > 391 K). It was found that the electrical conductivity in the amorphous Fe/TiO2 films obeys the Meyer–Neldel rule. The origin of this behavior is explained on the basis of the multiphonon-assisted hopping model.
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Acknowledgment
This work was supported by CNCSIS Contract PCCE-ID_76/2010. Petronela Rambu and Daniel Florea acknowledge the financial support from the Romanian programs POS-DRU/89/1.5/S/49944 and POSDRU/CPP 107/DMI 1.5/S/78342, respectively.
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Mardare, D., Yildiz, A., Apetrei, R. et al. The Meyer–Neldel rule in amorphous TiO2 films with different Fe content. Journal of Materials Research 27, 2271–2277 (2012). https://doi.org/10.1557/jmr.2012.193
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DOI: https://doi.org/10.1557/jmr.2012.193