Structural and physical properties of praseodymium based manganite systems

The structural and physical properties of Sr-doping in manganite perovskite oxides with the formula Pr1-xSrxMnO3Fy (x = 0.2, 0.3, 0.4 and 0.5) were investigated in this study. The samples were fabricated by the utilization of the solid-state reaction technique and were investigated by using X-ray diffraction, scanning electron microscope, and resistivity measurements as a function of temperature at constant dc magnetic fields. From x-ray powder diffraction measurements, all ceramics showed orthorhombic structure with space group N: 62 phases, and a second phase with space group N:141 appeared with sample Pr0.5Sr0.5MnO3. The investigation of the scanning electron microscope (SEM) revealed that as the Pr content of samples decreases the grain size of the samples decreases. The resistivity was measured for all samples under 0 T and 1 T dc magnetic field as a function of temperature. From these measurements, the insulator-metal transition temperature was obtained from the inflection point of (dp/dt) plots, and it was found that T MI shifted to higher temperatures as Sr content increased as noted in Pr0.5Sr0.5MnO3 the TMI = 315 K. The magnetoresistance was found at about 39% for the sample with x = 0.3 with decreasing the praseodymium concentration lower MR% values were observed. The results obtained in this study show that the Pr-based manganites are promising materials to be used in temperature sensing devices.