Effects of Ru substitution on the structural, magnetic and magnetocaloric properties of Pr0.68Ca0.22Sr0.1Mn1-xRuxO3(x=0, 0.05, 0.1 and 0.2) compounds


Pektas M., İZGİ T. , GENÇER H. , ATALAY S. , KOLAT V. S. , BAYRİ N.

JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS, cilt.31, ss.15731-15741, 2020 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 31 Konu: 18
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1007/s10854-020-04135-7
  • Dergi Adı: JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
  • Sayfa Sayıları: ss.15731-15741

Özet

The structural, magnetic and magnetocaloric properties of polycrystalline Pr0.68Ca0.22Sr0.1Mn1-xRuxO3(x = 0, 0.05, 0.1 and 0.2) compounds were studied. All the samples crystallized in an orthorhombic symmetry. A significant increase in the lattice parameters in the doped samples was attributed to the existence of Ru with a the mixed-valence state (Ru3+/Ru4+). The increase in the Curie temperature (T-c) with increasing Ru content was interpreted as Ru doping promoting the ferromagnetic interactions between Ru4+-Mn(3+)and Ru4+-Mn(4+)pairs. The decrease in saturation magnetisation was attributed to an AFM interaction between the Ru3+-Mn(3+)and Ru3+-Mn(4+)pairs and smaller magnetic moments of Ru than those of Mn. The decrease in |Delta S-M| (from 4.66 J kg(-1) K(-1)forx = 0.05 to 2.32 J kg(-1) K(-1)forx = 0.2 at 5 T) was attributed to the nature of phase transition (from a first-order to second-order transition) and a decrease in the saturation magnetisation.