Room temperature magnetocaloric and magneto-transport properties of monovalent doped Pr0.6Sr0.35Na0.05MnO3 manganite

The orthorhombic Sr-doped manganite Pr0.6Sr0.35Na0.05MnO3 synthesized using the conventional solid state reaction at high temperature is characterized by magnetic and electron transport studies. Structural data shows that crystallite size (32 nm) is found to be 15 times smaller than the mean grain size (500 nm). Magnetic measurements reveal the strong magnetocaloric effect in vicinity of the Curie temperature TC = 300 K. The considerable magnetic entropy change |ΔSMmax| = 1.84 J/(kg K) found for an applied magnetic field of 2 T results in large relative cooling power RCP with a maximum value of 92 J/kg. Peculiar temperature variation of electrical resistivity and negative magnetoresistance are discussed and related to grain sizes and grain boundaries.

► Characterization of new monovalent doped manganite Pr0.6Sr0.35Na0.05MnO3 with crystallite size of 32 nm.
► Metal-semiconductor transition shifts from 165 to 182 K for magnetic field 0–1 T.
► Negative magnetoresistance reaches 25% at 25 K.
► Maximum magnetic entropy change achieves 1.84 J/(kg K) for 2 T and RCP is 92 J/kg.
► Manganite is suitable for magnetic refrigeration technology at room temperature.