Energy storage and magnetoelectric coupling in neodymium (Nd) doped BiFeO3-PbTiO3 solid solution

Crystalline samples of 0.6Bi1-xNdxFeO3-0.4PbTiO3, or (BNFPT)x, were produced using the solid-state reaction technique with x = 0.05, 0.10, 0.15, and 0.20. The structural analysis revealed a structural transition from rhombohedral to tetragonal induced by Nd doping, which was further confirmed by Rietveld refinement analysis. The average grain size decreases from 1.46 mu m to 1.09 mu m with increasing Nd concentration. A ferroelectric relaxor-type behavior of the samples is observed as Nd content rises. The magnetization in-creases with increasing Nd doping concentration, caused by structural distortion and partial destruction of the spin cycloidal structure of BiFeO3. The temperature-dependent magnetization is found to decrease with increasing temperature and is an irreversible effect. Leakage current is reduced by three orders of magni-tude, from 10-3 to 10-6, with Nd doping for the studied doping concentrations. An enhanced polar-ization-electric field (P-E) hysteresis loops have been observed with a low value of remnant polarisation as Nd concentration increases. The P-E loops shows that the energy storage density of the BFO-PTO solid solution rises with increasing Nd concentration up to 0.15 and then decreases. The maximum recoverable energy storage density (Wrec) and efficiency (eta) for the 0.15 composition are 4.54 mJ/cm3 and 79 %, re-spectively. Conversely, as the concentration of Nd rises, the piezoelectric coefficient falls and follows the opposite trend as that of energy storage density. The magnetoelectric (ME) coupling coefficient increases with Nd doping. These results suggest that the investigated materials may be suitable for memory and energy storage devices. (c) 2023 Elsevier B.V. All rights reserved.

Automated summary

Crystalline samples of (BNFPT)x with x = 0.05, 0.10, 0.15, and 0.20 were produced using the solid-state reaction technique, revealing a structural transition induced by Nd doping. The average grain size decreased with increasing Nd concentration. As Nd content increased, a ferroelectric relaxor-type behavior, increased magnetization, and reduced leakage current were observed. Enhanced polarization-electric field hysteresis loops were observed with increasing Nd concentration, indicating a rise in energy storage density up to x = 0.15. The investigated materials show potential for memory and energy storage devices.