Synthesis, structural and transport properties of Pr0.75Na0.25Mn1−xFexO3 (0.0 ≤ x ≤ 0.3)

The single-phase polycrystalline perovskites Pr0.75Na0.25Mn1−xFexO3 (0 ≤ x ≤ 0.30) were prepared for the first time by a sol–gel technique, which offers shorter sintering time and lower temperature to avoid the volatilization of Na and the precipitation of manganese oxide. As a result, the maximum sodium solubility in Pr1−xNaxMnO3 and the degree of single-phase are significantly improved. The scanning electron microscope (SEM) results reveal that the sol–gel-derived compounds are agglomerated with fine primary particles. Both undoped and doped samples show two active IR vibrational modes at ∼426 and ∼607 cm−1. The resistivity of the samples series exhibits insulator behavior. The resistivity decreases with increasing Fe doping for x ≤ 0.05, and increases subsequently with further increasing Fe doping. The effects of Fe doping on Pr0.75Na0.25Mn1−xFexO3 compounds can be analyzed from two different aspects, namely the geometric effect (size of the dopant) and electronic configurations.