Studies of Structural, Impedance, Modulus Spectroscopy, and Magnetic Properties of Cr‐Modified SrTiO3 Perovskite Ceramic.

This study investigates the effects of chromium inclusion on the structural, microstructural, frequency dependent electrical and magnetic properties of SrTiO3 perovskite. The composition of Sr1−<italic>x</italic>Cr<italic>x</italic>TiO3 (SCT) ceramics with <italic>x</italic> = 0.00, 0.02, 0.04 is preapred via a high‐temperature solid‐state reaction route. Rietveld refinement of X‐ray diffraction data revealed a cubic structure with space group Pm3¯m$P m \bar{3} m$. All SCT samples have been analyzed for Cr incorporation at the Sr‐site using Raman and Fourier transform infrared spectroscopy. Field‐emission scanning electron microscopy studies probed a gradual increase in grain size due to the uniform distribution of dopants across sample surfaces, as confirmed by energy‐dispersive X‐ray spectroscopy analysis. Cr doping strongly influences the electrical properties of grain and grain boundary resistance. All samples undergo Arrhenius‐type transport via oxygen ion migration and mixed conduction (ionic/electron), whereas relaxation occurs through mixed‐type association (VO··−TiTi4+2+″$V_{\text{O}}^{\cdot \cdot} - \text{Ti}_{\left(\text{Ti}\right)^{4 &amp;amp;amp;plus;}}^{2 &amp;amp;amp;plus;} ^{&amp;amp;amp;aposx; &amp;amp;amp;aposx;}$) and (2CrSr.−TiTi4+2+″$2 \text{Cr}_{\text{Sr}}^{.} - \text{Ti}_{\left(\text{Ti}\right)^{4 &amp;amp;amp;plus;}}^{2 &amp;amp;amp;plus;} ^{&amp;amp;amp;aposx; &amp;amp;amp;aposx;}$). The magnetic nature of Cr‐doped samples confirms room‐temperature ferromagnetism due to carrier‐associated oxygen vacancies and Ruderman‐Kittel‐Kasuya‐Yosida interaction. These findings investigate Cr doping as mixed‐ionic and electronic conductors for intermediate temperature‐solid oxide fuel cells and spintronics‐based semiconductor devices. [ABSTRACT FROM AUTHOR]