High energy storage performance in lead-free BiFeO3-BaTiO3 ferroelectric thin film fabricated by pulsed laser deposition

In this work, the 0.68BiFeO3-0.32BaTiO3 (BFBT) ferroelectric thin film was fabricated with high maximum polarization for energy storage applications. BFBT thin film with pure perovskite phase was deposited on Pt/Ti/SiO2/Si substrates at 600°C by Pulsed Laser Deposition (PLD) method. We measured the ferroelectric hysteresis, dielectric properties and the fatigue performance of the BFBT thin film with thickness of about 200 nm. It was found that the film has a high maximum field-induced polarization value of 86 μC/cm2. Under an applied low electric field of 900 kV/cm, the recoverable energy density (Ure) could reach up to 19 J/cm3, and the energy efficiency (η) is around 51% at room temperature. Furthermore, the film shows outstanding fatigue endurance even after 1×107 cycles. All results suggest that lead-free BFBT ferroelectric thin film is very promising energy storage materials.