Dipole Relaxation in Semiconducting Zn2−xMgxInV3O11 Materials (Where x = 0.0, 0.4, 1.0, 1.6, and 2.0)

This paper reports on the electrical and broadband dielectric spectroscopy studies of Zn2−xMgxInV3O11 materials (where x = 0.0, 0.4, 1.0, 1.6, 2.0) synthesized using a solid-state reaction method. These studies showed n-type semiconducting properties with activation energies of 0.147–0.52 eV in the temperature range of 250–400 K, symmetric and linear I–V characteristics, both at 300 and 400 K, with a stronger carrier emission for the matrix and much less for the remaining samples, as well as the dipole relaxation, which was the slowest for the sample with x = 0.0 (matrix) and was faster for Mg-doped samples with x > 0.0. The faster the dipole relaxation, the greater the accumulation of electric charge. These effects were analyzed within a framework of the DC conductivity and the Cole–Cole fit function, including the solid-state density and porosity of the sample. The resistivity vs. temperature dependence was well fitted using the parallel resistor model. Our ab initio calculations also show that the bandgap increased with the Mg content.

Equivalent circuit modeling on defect-dipole enhanced dielectric permittivity

A new equivalent circuit describing enhanced permittivity associated with non-Debye defect-dipole relaxation.