Enhanced magnetocaloric performance with room-temperature transition in Bi-substituted La0.65Ca0.20Pb0.15Mn1-xBixO3 (x = 0.0, 0.01, 0.03, and 0.05) perovskites


Toyganözü D., KILIÇ ÇETİN S., AKÇA G., EKİCİBİL A.

Journal of Materials Science: Materials in Electronics, cilt.37, sa.2, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 37 Sayı: 2
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s10854-025-16527-8
  • Dergi Adı: Journal of Materials Science: Materials in Electronics
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Applied Science & Technology Source, Chemical Abstracts Core, Compendex, INSPEC, MEDLINE, Engineering Source (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
  • Çukurova Üniversitesi Adresli: Evet

Özet

The impact of Bi substitution at the Mn-site on the structural, magnetic, and magnetocaloric characteristics of La0.65Ca0.20Pb0.15Mn1−xBixO3 (x = 0.0, 0.01, 0.03, and 0.05) perovskites has been systematically examined. X-ray diffraction (XRD) results confirmed that all samples were found to crystallize in a rhombohedral crystal structure with space group R3¯c. Thermomagnetic measurements revealed a progressive reduction in the Curie temperature (TC) with increasing Bi concentration, decreasing from 322 K for the parent phase to 289 K for the highest doping level, shifting the magnetic transition closer to room temperature, which is desirable for practical refrigeration applications. Conversely, the magnetic entropy change (− ΔSM) exhibited a steady enhancement, increasing from 4.18 Jkg−1 K−1 at x = 0.0 to 5.06 Jkg−1 K−1 at x = 0.05 under a field change of 5 T. The relative cooling power (RCP) exhibited a non-monotonic dependence on doping, with the maximum value of 245.78 Jkg−1 obtained for the parent sample, suggesting an optimal balance between entropy change and transition width. Arrott plot analysis confirmed that all compositions undergo a second-order magnetic transition. These results indicate that Bi doping is an efficient strategy to lower TC​ toward room temperature while simultaneously enhancing the magnetocaloric effect, highlighting the potential of these compounds for magnetic refrigeration (MR) near room temperature.