Structural, optical and electrical properties of Mn-doped ZnFe₂O₄ synthesized using sol–gel method

The system Zn_1-xMn_xFe₂O₄ (x = 0, 2, and 4%) was prepared by sol–gel chemical route at 80 °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. The surface charge and morphology of the samples were studied using zeta potential and scanning electron microscope analysis, respectively. The optical bandgap of the samples suggested that they were semiconducting. The dielectric characteristics of samples were examined as a function of temperature (60–600 °C) at various frequencies (1 kHz, 10 kHz, 100 kHz, and 1 MHz). The presence of interfacial and orientational polarization was indicated by dielectric constant and dissipation factor studies, which ranged from (0.7–460) to (0.3–0.8) with Mn and were found thermally stable up to 300 °C. The thermal dependence of DC conductivity demonstrates Arrhenius type transport with one, two, and three regions of conduction in sample ZF-0, ZF-2, and ZF-4 respectively. The sources of charge carriers in samples were \({V}_{o}^{\cdot \cdot }\), \(e^{\prime}\) and dipole defects \(\left( {V_{o}^{{ \cdot \cdot }} - 2{Fe_{{Fe^{{3 + }} }}^{{2 + }}} ^{\prime } } \right)\)/\(\left( {{2Mn^{{3 + }} _{Zn^{{2 + }} }}^.- 2{Fe_{{Fe^{{3 + }} }}^{{2 + }}} ^{\prime } } \right)\). The current work could help to identify the possible applications in semiconductor devices, thermally stable capacitors, and as mixed ionic electronic conductors in solid oxide fuel cells.