Structural, Ferroelectric, and Ferromagnetic Properties of Yttrium-Doped Cobalt Ferrites to Produce Green Electricity by Hydroelectric Cells

A hydroelectric cell has been coined as an accomplished device keeping the ability to produce current just by adsorbing a few microliters of water. These cells are the new source of generating green energy which involves no evolution of toxic gases like NO₂, SO₂, CO, etc. Our current research focuses on studying how to increase the maximum output current (I) in the pure cobalt ferrites by doping with rare-earth ion, yttrium. The yttrium-doped cobalt ferrites with composition (CoY_xFe_2−xO₄, x = 0.00, 0.10, and 0.20) have been prepared using a modified sol–gel citrate method. X-ray diffractogram (XRD) confirmed the formation of cubic crystal structures with crystallite size less than 30 nm. Energy dispersive x-ray (EDX) patterns confirmed the presence of elements (Y, Co, Fe, O) in the prepared compositions. The ionic diffusion mechanism confirmed the dissociation of water molecules by the cations present on the surface of the material at room temperature. Vibrating sample magnetometer (VSM) analysis revealed the increase in coercivity values from 948.81 Oe to 2580.09 Oe with the increase in the concentration of yttrium ions in the cobalt ferrite (CFO) lattice. The V–I polarization curves measured the maximum output current and voltage as around 8.6 mA and 1.1 V, respectively, for the 20% yttrium-doped CFO hydroelectric cells (area = 4 cm²).