Energy storage in BaBi4Ti4O15 thin films with high efficiency.

A ferroelectric film with slim polarization-electric (P-E) hysteresis loops, showing small remanent polarization (P r) and large saturated polarization (P s), is desired to obtain high recoverable energy density (U r e ) and efficiency (η) in thin film capacitors. Here, small P r and large P m values are achieved in BaBi 4 Ti 4 O 15 thin films through modulating film grain size. A large U r e of 44.3 J / cm 3 as well as a high η of 87.1% is obtained. In addition, the derived BaBi 4 Ti 4 O 15 thin films show excellent energy storage performance in wide frequency range, thermal stability, and fatigue endurance. These results suggest that BaBi 4 Ti 4 O 15 films can be considered as a candidate for dielectric energy storage capacitors, and the route through grain size optimization is a promising strategy to improve the capacitive performance of ferroelectric materials. [ABSTRACT FROM AUTHOR]