Dielectric, Impedance, Magnetic and Magnetocapacitance Investigations in ferrite-manganite nanocomposites for Hydroelectric Cell applications

In this work, nanoparticles of CoFe2O4 and La0.67Sr0.33MnO3 and nanocomposites (1 - x)CoFe2O4 - (x)La0.67Sr0.33MnO3 (for x = 0.10, 0.20, 0.30) have been made through sol-gel route and solid-state route, respectively. The structural analysis via X-ray diffraction (XRD) displays formation of spinel CoFe2O4 (CFO) having crystallite size 35 nm and rhombohedral La0.67Sr0.33MnO3 (LSMO) having crystallite size 15 nm. Field emission scanning electron microscope and energy-dispersive X-ray analysis (FESEM-EDAX) shows the particle size of 51.35 nm and 24.77 nm for CFO and LSMO, respectively. The particle size and crystallite size decreased in CFO-LSMO nanocomposites with increase in LSMO content. The dielectric measurements display strong Maxwell-Wagner polarization and display strong composition dependence attributed to homogenous distribution of LSMO as well as non-pinning of domain wall of CFO. The impedance spectroscopy displayed thermally activated conduction mechanism. The magnetocapacitance measurements displayed improvement in magnetoelectricity with LSMO content. The hydroelectric cell of CFO-LSMO nanocomposites exhibited a strong correlation between the content of LSMO and the efficiency of the cell. The 0.7LSMO-0.3CFO composite exhibited improved performance in hydroelectric cell as can be observed from drastic difference in impedance from 8x104 to 3x103 Hz. These improvements in the structural, electrical, magnetocapacitance and hydroelectric cell performance with LSMO in the prepared composites suggest their potential use in magnetoelectric and hydroelectric devices.