The oxide Sr₂MnO₄ was synthesized using the solid-state reaction technique. Quenching in air from 1500 C to room temperature yielded the pure phase powder of Sr₂MnO₄. The purity of synthesized powder was further examined by FTIR analysis. The Rietveld refinement of XRD data confirmed the tetragonal structure and I4/mmm space group. The band gap, computed from the Tauc’s plot, was found to be 1.15 eV. The XPS analysis depicted the presence of Mn³⁺ and Mn⁴⁺ valence states. Measurement of the AC electrical conductivity over wide temperature (30 C–500 C) and frequency (0.020–2 MHz) ranges were carried out. The conduction mechanism changed from small polaron tunnelling (<270 C) to non-overlapping large polaron tunnelling (>270 C). The frequency versus imaginary part of the impedance (Z″) and modulus (M″) plots exhibited a change in the conduction domain with increase in temperature. This result was further verified by the Ghosh’s scaling of the conductivity spectra.

使用固态反应技术合成了氧化物Sr ₂ MnO ₄。在1500℃至室温的空气中淬火，得到Sr ₂ MnO ₄的纯相粉。合成粉末的纯度通过FTIR分析进一步检查。XRD数据的Rietveld细化证实了四方结构和I4 / mmm空间群。根据Tauc曲线计算得出的带隙为1.15 eV。XPS分析描述了Mn ³⁺和Mn ⁴⁺的存在价态。在宽温度（30 C–500 C）和频率（0.020–2 MHz）范围内进行了交流电导率的测量。传导机制从小极化子隧穿（<270 C）变为非重叠大极化子隧穿（> 270 C）。阻抗（Z”）和模量（M”）图的频率相对于虚部的变化随温度的升高而呈现出传导域的变化。电导率谱的戈什定标进一步证实了这一结果。