Enhanced Dielectric and Energy Storage Performance in Lithium-Modified Sodium Niobate Perovskites

Lead-based ceramics have been extensively used in energy applications, yet their environmental toxicity and regulatory challenges remain significant issues. Herein, a lead-free bulk ceramic-based material composed of “Na (1−x) Li (x) NbO 3 ,” 0.00 ≤ x ≤ 0.15 was synthesized through mixed oxide route, followed by calcination and sintering to achieve phase purity and densification. The optimized composite with x = 0.05 exhibits significant energy storage density of roughly 1.5 μJ cm −3 and an exceptionally high energy storage efficiency of 88.7% accompanied by the narrower polarization-electric field curves. These results were achieved under a modest electric field of 1 kV cm −1 with a doping ratio (x) of 0.05 mole. In addition, the dielectric properties were evaluated using impedance spectroscopy, providing valuable insights for the design of efficient energy storage systems. For detail investigations, different analytical techniques have been utilized to confirm the crystal structure phase identification, grain size and the composite formation. The obtained results underscore the promising potential of lead-free ceramics for future energy storage technologies.