Transport properties and conduction mechanisms in CuFe2O4 and Cu1−xZnxGa0.3Fe1.7O4 compounds
| Autor: | S.S. Ata-Allah, M. Yehia |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Materials science
Condensed matter physics business.industry Transition temperature Spinel Analytical chemistry Conductivity engineering.material Condensed Matter Physics Thermal conduction Polaron Electronic Optical and Magnetic Materials Semiconductor Octahedron Electrical resistivity and conductivity engineering Electrical and Electronic Engineering business |
| Zdroj: | Physica B: Condensed Matter. 404:2382-2388 |
| ISSN: | 0921-4526 |
| Popis: | Single-phase structure of CuFe2O4 and Cu1−xZnxGa0.3Fe1.7O4; with (0.0≤x≤0.5) are synthesized. Electrical conductivity measurements as a function of temperature are carried out in the frequency range (102–105 Hz) for the prepared samples. The obtained results of these materials reveal a metallic-like behavior in the low range of frequency. At high frequency regime metallic-to-semiconductor transition has been observed as the compositional parameter x increases. Metallic-like behavior is accompanied with samples having low Zn content, where cation–cation [Cu–Cu] interaction is major at the octahedral B-sites and semiconductor behavior is associated with compounds having high Zn content, where cation–anion–cation [Fe–O–Fe] interaction is most predominant at B-sites in these spinel oxides. All studied compositions exhibit a transition with change in the slope of conductivity versus temperature curve. This transition temperature is found to decrease linearly with increasing Zn concentration x. The relation of the universal exponent s with temperature indicates the presence of two hopping conduction mechanisms; the correlated barrier hopping CBH at low Zn content x≤0.2 and small polaron (SP) at Zn content x≥0.3. |
| Databáze: | OpenAIRE |
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