No abstract

Samples with doping of Mn (0, 2, and 4%) in ZnFe2O4 were prepared by sol-gel chemical route at 80 o C. X-ray powder diffraction and Raman spectrum analysis were used to determine the preliminary phase of obtained samples. W-H and SSP plots were used to determine the crystallite size and micro-strain of samples. Using zeta potential and scanning electron microscope, the surface charge and morphology of the prepared samples were studied. The optical bandgap of sample suggested that it was semiconducting.The dielectric characteristics of samples were examined as a function of temperature at various frequencies (1 KHz, 10 KHz, 100 KHz, and 1 MHz) (60-600 o C). Dielectric study revealed the presence of interfacial and orientational polarization, with dielectric constants and dissipation factors ranging from (0.7-460) to (0.3-0.8), remain thermally stability up to 300 o C. In samples ZF-0, ZF-2, and ZF-4, the thermal dependence of DC conductivity demonstrates Arrhenius transport with one, two, and three regions of conduction, respectively. The sources of charge carrier in samples were ⋅⋅ , ′ and dipole defects ( ⋅⋅ − 2 2+ 3+ ′ ) and (2 3+ 2+ . − 2 2+ 3+ ′ ). The current work could help identify possible applications in semiconductor devices, thermally stable capacitors, and as mixed ionic electronic conductors in solid oxide fuel cells.

Samples with doping of Mn (0, 2, and 4%) in ZnFe2O4 were prepared by sol-gel chemical route at 80oC. X-ray powder diffraction and Raman spectrum analysis were used to determine the preliminary phase of obtained samples. W-H and SSP plots were used to determine the crystallite size and micro-strain of samples. Using zeta potential and scanning electron microscope, the surface charge and morphology of the prepared samples were studied. The optical bandgap of sample suggested that it was semiconducting. The dielectric characteristics of samples were examined as a function of temperature at various frequencies (1 KHz, 10 KHz, 100 KHz, and 1 MHz) (60-600oC). Dielectric study revealed the presence of interfacial and orientational polarization, with dielectric constants and dissipation factors ranging from (0.7–460) to (0.3–0.8), remain thermally stability up to 300oC. In samples ZF-0, ZF-2, and ZF-4, the thermal dependence of DC conductivity demonstrates Arrhenius transport with one, two, and three regions of conduction, respectively. The sources of charge carrier in samples were Vo,e1 defects (Vo - 2FE2+ Fe3+') and (2M3+ Zn2+ - 2FE2+ Fe3+'). The current work could help identify possible applications in semiconductor devices, thermally stable capacitors, and as mixed ionic electronic conductors in solid oxide fuel cells.

The conventional ceramic route has been used to prepare the La-doped Ba2SnO4 samples by heat-treatment at 1000oC and sintered at 1250oC. The phase identification was carried out using XRD and found to be single phase up to 4 atoms %. The solubility of La at Ba-site were further reconfirmed using FTIR and Raman analysis. The AC conductivity spectra of all samples follow universal Johnscher’s power law; however, the thermal dependence of suggest Arrhenius type conduction within the sample. Further, the scaled conductivity and frequency at all temperatures superimposes on a single master curve, indicates the invariance of conduction mechanism. The impedance spectroscopy studies suggest the major contribution of grain in the conduction and relaxation. The present material could be potentially used in semiconductor device, UV-detector, and mixed ionic and electronic conductor (MIECs) by utilizing absorption states and thermo-curves as metastable state.