Achieving high-energy storage performance in 0.67Bi1-xSmxFeO3-0.33BaTiO3 lead-free relaxor ferroelectric ceramics

Abstract

BiFeO3–BaTiO3 (BF-BT)-based lead-free ferroelectric ceramic has attracted immense interest in energy storage applications due to its great spontaneous polarization (Pmax) strength. However, high remanent polarization (Pr) has become a serious obstruction for its practical application. In this work, Sm ions were doped into 0.67BiFeO3-0.33BaTiO3 (0.67Bi1-xSmxFeO3-0.33BaTiO3, BSxF-BT) to tailor the structure and energy storage properties. It was found that the doping of Sm ions effectively reduced Pr by enhancing the relaxor behavior of BF-BT ceramic, which produce an enhancement in the energy storage performance. Large recoverable energy storage density Wrec of 2.8 J/cm3 with moderate energy storage efficiency η of 55.8% (200 kV/cm) were achieved in the ceramics with x = 0.1. Moreover, the energy storage capabilities exhibited good stability at temperature (20–95 °C) and frequency (0.1–50 Hz). Furthermore, the ceramic also possessed a predominant discharge speed with a discharge time less than 0.1 μs in a circuit with a load of 200 Ω. These results showed that the Wrec and η of BF-BT ceramic could be availably promoted by the doping of Sm ions, which may be helpful for the enhancement of energy storage performance of BF-BT-based ceramics.