Study on the structural transition and inverse magnetocaloric effect of Dy-substituted Pr 0.5 Sr 0.5 MnO 3

The investigation focused on the structure, magnetic properties, and inverse magnetocaloric effect (IMCE) of Pr 0.5- x Dy x Sr 0.5 MnO 3 (x = 0.00, 0.05, and 0.10) synthesized via the traditional solid-state reaction approach. The in -situ X-ray diffraction analysis revealed a transition from tetragonal to monoclinic structure within the temperature range of 170 - 180 K in Pr 0.4 Dy 0.1 Sr 0.5 MnO 3 . Upon Dy 3+ doping, phase separation occurred, leading to an increased antiferromagnetic (AFM) phase and a reduced ferromagnetic (FM) phase. During the magnetic and structural phase transitions, a minor hysteresis and significant IMCE were observed. The negative change in magnetic entropy ( -Delta S M ) associated with IMCE rose from -2.2 to -6.0 J/kg K, and the relative cooling power ( RCP ) increased from 45.5 to 160.7 J/kg with higher Dy 3+ content under a magnetic field change of 50 kOe. The large IMCE obtained is attributed to the enhanced magnetostructural coupling during the magnetic phase transition due to Dy 3+ substitution. Our work provides a scheme for qualitatively studying magneto -structural coupling in manganites, which might be important for utilizing materials with large IMCE.