In this investigation, our primary objective is to explore the structural, morphological, and electrical characteristics of Bi_0.75Ba_0.25(FeMn)_0.5O₃ ceramic material synthesized by the sol-gel method. The prepared sample underwent synthesis through the conventional sol-gel technique. Examination through X-ray diffraction (XRD) unveiled a well-defined rhombohedral structure within the R$\acute{3}$C space group. Moreover, to evaluate the purity and nano-grain morphology, we utilized energy dispersive spectroscopy (EDX) and scanning electron microscopy (SEM). Electrical assessments were carried out over a frequency span of 100 Hz to 1 MHz and temperatures ranging from 200 to 340 K. Employing the correlated barrier hopping (CBH) model, we analyzed the AC conductivity of our specimen. The activation energy, determined from both DC conductivity and impedance spectra, demonstrated close correspondence, suggesting that both conductivity and r laxation processes are influenced by similar factors. Notably, the dielectric properties hold significant importance, potentially rendering our sample suitable for electronic applications. Furthermore, we calculated thermodynamic parameters, such as enthalpy (ΔH), entropy change (ΔS), and free energy of activation (ΔF), offering deeper insights into the material’s behavior and conductivity mechanisms.

Resistive gas sensors are widely utilized to detect a variety of gases including poisonous, explosive, biomarker, and even non-toxic gases because of their exceptional performance. Zinc stannate (Zn₂SnO₄) is a ternary metal oxide with exceptional stability and distinctive electrical characteristics. In a variety of morphologies and along with other materials, it has been utilized to realize resistive gas sensors. Here, we thoroughly explain the gas sensing characteristics of Zn₂SnO₄ gas sensors in pristine, doped, and composite forms. Also, we have emphasized in sensing mechanism to further understand the gas sensing principle of Zn₂SnO₄ gas sensors.