Enhancement of energy storage efficiency in lanthanum and cobalt co-doped BiFeO₃ nanomaterials

Lanthanum and cobalt-incorporated BiFeO₃ (BFO) nanomaterials have been prepared and their structural, dielectric, and multiferroic properties have been reported here. Bi_1-xLa_xFe_1-xCo_xO₃ (x = 0, 0.03, 0.06, 0.09, 0.12) nanomaterials have been synthesized successfully through a simple solvothermal technique. XRD and Rietveld refinement analysis using the FullProf Software confirms that all synthesized materials follow the rhombohedral perovskite crystal structure of the R3c space group. The variations of dielectric properties with frequency at room temperature and with temperature at different frequencies have been observed for the temperature range 35 °C to 360 °C. Impedance analysis has also been performed to indicate the contributions of grain, grain boundary, etc. of the samples in the electrical conduction process. The Nyquist plot gives information on the conduction mechanism of all synthesized samples, where grain, grain boundary, and electrode effects are present. The frequency-dependent AC conductivity behavior strongly follows Jonscher’s universal law. The enhancement of magnetic properties has been observed for the doped samples from the study of room temperature magnetic hysteresis loop using SQUID. The improvement in magnetoelectric coupling and energy storage efficiency has been observed for doped nanocompounds from the measurement of magneto-capacitance and P-E loop, respectively. The observed properties of the co-doped BFO nanomaterials are very useful for energy storage and spintronic devices.