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In this current study, we present a detailed investigation on the structural, magnetic, magnetocaloric and electrical properties for La0.4Ag0.1Ca0.5MnO3 (S1) and La0.5Ca0.4Ag0.1MnO3 (S2) polycrystallines samples prepared using the well-known sol–gel method. Our analysis of X-ray diffraction, employing Rietveld refinement, reveals that these samples crystallize in the orthorhombic structure with Pnma space group. The results demonstrated that magnetization measurements as a function of temperature, under different magnetic fields for the sample (S1), exhibit two distinct phase transitions at TC1 = 48 K and TC2 = 186 K, whereas sample (S2) displays a single transition at 261 K. Based on the magnetic field dependence of magnetization, M(H), and applying the thermodynamic Maxwell equation, the magnetic entropy change |ΔSm| of the studied samples (S1) and (S2) was determined. Electrically, we observed an upturned region of resistance at low temperature, and this recovery of the resistance is significantly influenced by the external magnetic field. [ABSTRACT FROM AUTHOR]

This study investigates the structural, electrical, and dielectric properties of GdCrO 3 (GCO) compounds. X-ray diffraction analysis confirmed the formation of the perovskite phase of GCO, crystallizing with the Pbnm space group. Scanning electron microscopy (SEM) was employed to examine the morphology and chemical composition of the powder, ensuring compound homogeneity, while transmission electron microscopy (TEM) provided insights into the internal structure and finer morphology of the GCO sample. Electrical measurements revealed that GCO exhibits semiconductor behavior, with a notable increase in conductivity as temperature rises, attributed to enhanced charge carrier mobility and hopping conduction mechanisms. Dielectric analysis demonstrated significant frequency-dependent behavior, characterized by various polarization effects and relaxation phenomena. GCO is a promising material for energy storage due to its giant permittivity and low energy loss. The activation energies derived from the electrical and dielectric measurements indicate higher resistance within the grains compared to the grain boundaries, suggesting complex conduction processes. Additionally, the dielectric loss spectra revealed substantial losses, likely due to defect states such as oxygen vacancies and mixed valence states, indicating a highly disordered material. These comprehensive insights into the structural and functional properties of GCO highlight its potential applications in electronic and electrical devices where controlled conductivity and dielectric properties are crucial., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)