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Electrical properties of copper phosphate glasses II. Dielectric properties

1986; Elsevier BV; Volume: 79; Issue: 3 Linguagem: Inglês

10.1016/0022-3093(86)90233-4

1873-4812

Alicia Durán, JoséR. Jurado, JoséM. Fernandez Navarro,

Luminescence Properties of Advanced Materials

The ac and dc electrical properties of the P2O5BaOCuO glass system have been measured. TSPC and TSDC experiments and dc conductivity as a function of time indicate the predominantly electronic character of these glasses. The conduction process can be basically explained by a polaron hopping model in an adiabatic regime. Conductivity values which depend on the glass microstructure and switching phenomena are observed. The filamentary-feature of this process suggests a Poole-Frenkel mechanism. A Debye dielectric relaxation non-simple process is deduced from the frequency and temperature dependence of loss tangent and dielectric constant. The activation energies agree with those determinated from dc measurements, suggesting a unique electronic hopping conduction mechanism in both regimes. The ac and dc electrical properties are strongly affected by the glass composition and essentially by the redox Cu+/Cut ratio. A conduction model accounting for ac and dc behaviour is finally proposed.