Enhanced Energy Storage Properties in Lead-Free 0.92(Bi_0.5Na_0.5)TiO₃–0.08BaTiO₃ Ceramics via Ce Doping

Abstract

Lead-free (Bi_0.46Na_0.46Ba_0.08)Ti_1-xCe_xO₃ (abbreviated as BNBT-xCe, x = 0.01–0.04) ceramics were prepared via conventional solid-state mixed oxide technique. The role of B-site Ce doping was investigated through systematic studies of crystal structure, microstructure, dielectric, ferroelectric and energy-storage properties. All samples exhibited pseudocubic symmetry with an observance of single-phase perovskite structure up to x = 0.02. The SEM micrographs displayed dense microstructure with an average grain size that tended to decrease with increasing Ce doping content. With increasing x, suppression of maximum relative permittivity (ε_m) and increased broadening of the T_m peak were observed. The change from a square-like ferroelectric to a relaxor-like slim P-E hysteresis loop with a significant drop of P_r was observed at compositions with x ≥ 0.01. Analysis of energy-storage properties revealed the maximum recoverable energy-storage density (W_rec) of 0.28 J/cm³ under applied electric field of 50 kV/cm at x = 0.01. The results demonstrate that Ce modified BNBT ceramics are promising candidate for lead-free energy-storage capacitor applications.

Keywords:

• Lead free BNT-BT
• cerium doping
• dielectric property
• energy-storage property

Additional information

Funding

This work is financially supported by National Science Research and Innovation Fund (NSRF) through Naresuan University (R2564B001). The authors would also like to thank Michelle Jennings for language editing and proofreading.