Multifunctional Nd3+ substituted Na0.5Bi0.5TiO3 as lead-free ceramics with enhanced luminescence, ferroelectric and energy harvesting properties

Herein, we present comprehensive investigations of the optical and electrical properties of Nd3+ substitution in sodium bismuth titanate ceramics (NBNT) with varying Nd3+ concentration. The room temperature photoluminescence (PL) emission for both unpoled and poled samples is observed to be a maximum for an Nd3+ substitution of 1 mol%. Upon poling, the PL intensity is observed to be quenched, consistent with the obtained XRD data, indicating an electric-field induced structural ordering towards higher symmetry, confirmed with the help of structural refinement. The evaluated ferroelectric to relaxor and antiferroelectric relaxor T(F–R) was observed clearly from the poled dielectric–loss curve for the 1 mol% of Nd3+ substitution. Furthermore, the optimized NBNT exhibited a lower Ec and a higher off-resonance figure of merit (FOMoff) for energy harvesting by 12% and 30%, respectively, in comparison with un-doped NBT