Dielectric and energy-storage properties of NaNbO3–NdFeO3 ceramics

The design of high-performance dielectrics is critical for next-generation capacitors and electronic devices. Herein, (1-x)NaNbO3-xNdFeO3 bulk ceramics were synthesized to investigate the effects of Nd3+/Fe3+ substitution on their dielectric and energy-storage properties. It is revealed that the narrow single polarization–electric field (P–E) loop evolved from double loops to enhance energy-storage performances with increasing x. The maximal recoverable energy-storage density of 1.673 J cm−3 and the efficiency of 76.7% were obtained at x = 0.06 and 0.08, respectively. Moreover, a negative relative permittivity in specific frequency ranges was the answer for the oscillation of domain walls. These results not only suggest that the substitution of Nd3+/Fe3+ optimizes the energy-storage properties of NaNbO3-based ceramics, but also provides a feasible strategy for functional design in electromagnetic metamaterials.