Effects of A, B-site multiple ion co-doping on the structure, magnetic, magnetocaloric effect, and critical behavior of La0.7-xNd0.1Sr0.2KxMn0.95Ni0.05O3 ceramics

The effects of K+ doping on structure, magnetic characteristics, magnetocaloric properties, and critical behavior of La0.7-xNd0.1Sr0.2KxMn0.95Ni0.05O3 (LNSKMNO) ceramics (x = 0.00, 0.05, and 0.10) were investigated. The X-ray diffraction and refinement findings revealed that LNSKMNO exhibited a distinctive rhombohedral structure of the R-3c space group (No. 167). To validate the chemical composition of LNSKMNO ceramics, EDS spec-troscopy and X-ray photoelectron spectroscopy (XPS) were utilized. The magnetization of LNSKMNO exhibited a temperature-dependent behavior, revealing a phase transition from the ferromagnetic (FM) phase to the para-magnetic (PM) phase at approximately the Curie temperature (Tc). By utilizing normalization and Banerjee's criterion, the magnetic phase transition of LNSKMNO was determined to be a second order magnetic phase transition. The maximal magnetic entropy (-ASmaxM) of LNSKMNO around Tc was 4.24, 4.53, and 4.07 J/(kg K) at the 5 T external magnetic field (H). The Kouvel-Fisher approach and modified Arrott plot were used for determining the values of the critical exponents of & beta;, & gamma;, and & delta;. The critical exponents for LNSKMNO ceramics generally conformed to those obtained based on the Mean-field model.

Automated summary

The effects of K+ doping on the structure, magnetic characteristics, magnetocaloric properties, and critical behavior of LNSKMNO ceramics were investigated. The results showed that K+ doping influenced the structure and magnetic behavior of the ceramics, leading to temperature-dependent magnetic phase transition.