Near room temperature magneto-transport (TCR & MR) and magnetocaloric effect in Pr2/3Sr1/3MnO3:Ag2O composite

The magneto-transport and magnetocaloric effect in Pr2/3Sr1/3MnO3:Ag2O (PSMO:Ag) with Ag2O (10-30 mol%) have been studied by resistivity and magnetization measurements. Temperature coefficient of resistance (TCR), magneto-resistance (MR) and magnetocaloric properties of the composite have shown different responses to Ag addition. Rietveld refinement confirms single phase crystalline structure with orthorhombic Pbnm space group and presence of silver metal as well. TCR changes randomly with Ag, increasing initially to 7.8% K-1 for PSMO:Ag10 composite which then decreases marginally with increasing Ag content. MR has been found to reach a maximum value of 30.5% at 1 T applied field for PSMO:Ag10 composite. Magnetic entropy change (Delta S-M) increases with increasing Ag content and is found to be 3.5 J kg(-1) K-1 (1 T), 6.1 J kg(-1) K-1 (2 T) and 8.4 J kg(-1) K-1 (3 T) for PSMO:Ag30 composite at 285 K. The maximum refrigeration capacity of 39.5 J kg(-1) (1 T), 91.0 J kg(-1), (2 T) and 107.7 J kg(-1) (3 T) has been found for the PSMO:Ag20 composite. PSMO:Ag composite exhibits potential for bolometric, magnetic sensing and magnetic refrigerating applications near room temperature. (C) 2014 Elsevier B.V. All rights reserved.