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This paper covers a detailed study of the sintering temperature (TS) effect on the electrical and magnetotransport properties of Pr0.67Sr0.33MnO3 nanoparticles prepared by sol–gel method. The temperature dependence of resistivity displays a metal–insulator transition with increasing temperature. The electrical resistivity is strongly affected by particle size. The resistivity minimum at low temperature is associated to electron–electron coulombic interactions. Magnetotransport analysis was carried out using a phenomenological percolation model for all our samples. The obtained results indicate that a percolation model is not suitable for samples presenting high magnetic disorder. The magnetoresistance (MR) can be modulated by particle size effect. We have recorded considerable MR values (−MR(T) = 34% at 10 K for a 1T field when TS = 850°C, −MR(T) = 33% at 290 K for a 2T field when TS = 1000°C and −MR(H) = 33% at 5 K for a 1T field when TS = 700°C). The considerable MR values indicate the possibility of using these samples for several technological applications.

In this work, we report the effect of sintering temperature (TS) on the magnetic interactions and the critical behavior of Pr0.67Sr0.33MnO3 manganite prepared via sol–gel method (700 °C ≤ TS ≤ 1200 °C). The critical exponents study revealed that the 3D-Ising model is the best model to describe the magnetic interactions in the P1000 (TS = 1000 °C) and P1200 (TS = 1000 °C) samples. Consequently, a strong magnetic anisotropy characterizes these samples near the paramagnetic-ferromagnetic transition temperature, such anisotropy can be linked to the magnetic moment of Pr3+ ions (µ = 3.58 µB). For TS ≤ 850 °C, it becomes nearly impossible to speak about universality class due to the presence of great magnetic disorder induced by several factors like spin disordered shell in nanoparticles, magnetic frustration and Griffiths phase.

This paper covers a detailed study of the structural, morphological, magnetic, and magnetocaloric properties of Pr0.67Sr0.33MnO3 compound prepared via sol–gel method with different sintering temperatures (700 °C ≤ TS ≤ 1200 °C). The structural study revealed that all samples crystallize in the orthorhombic structure with Pnma space group, with the presence of some impurities for TS ≤ 850 °C. With increasing sintering temperature TS, the Curie temperature shifts from 256 to 290 K. The evolution of the magnetic properties may be explained in terms of the core–shell model. The disordered magnetic behavior induces a spin-glass-like state at low temperature with the presence of Griffiths phase above Curie temperature. Magnetocaloric study indicated a relative cooling power of 97.78 J/kg under 2 T magnetic field at room temperature for the sample sintered at 1000 °C, indicating that this sample is a suitable candidate for magnetic refrigeration.