Interlayer Coupling Enhanced Energy Storage Performance in a Flexible BMT-BTO/BMT Multilayer Ferroelectric Film Capacitor

Abstract

Flexible ferroelectric capacitors with high energy density and storage efficiency are highly desirable in the next generation of flexible electronic devices. To develop high-performance ferroelectric capacitors, a conventional approach is chemical modification. Here, a novel approach of interlayer coupling is proposed to achieve high energy storage performance in BiMg 0.5 Ti 0.5 O 3 -BaTiO 3 /BiMg 0.5 Ti 0.5 O 3 (BMT-BTO/BMT) N multilayer ferroelectric films fabricated on flexible mica substrates via a sol−gel coating method. The interlayer electrostatic coupling between the ferroelectric BMT and relaxor ferroelectric BMT-BTO layers leads to small remnant polarization and large breakdown field strength, resulting in an outstanding energy storage density of ∼106.8 J cm −3 and a good efficiency of ∼75.6% in the multilayer thin films. Further, the energy storage performance remains stable in a wide range of temperatures (25−200 °C) and frequencies (500 Hz to 10 kHz) after 10 8 electrical loading cycles. The energy storage performance also has no obvious deterioration when the multilayer film experiences 10 4 mechanical bending cycles with a bending radius of 4 mm. The approach proposed in the present work should be generally implementable in other multilayer flexible ferroelectric capacitors and offers a novel avenue to enhance energy storage performance by tuning the interlayer coupling.

Improved energy storage performance in flexible (PbLa)ZrO3 thin films via nanocrystalline engineering

“…In order to verify the applicability of flexible film capacitors, the temperature, frequency, mechanical bending and electric fatigue cycling stability are all important for the films operated under harsh working conditions. [41][42][43] The P-E loops of flexible (PbLa)ZrO 3 thin films measured at different temperatures, frequencies, bending cycles and electric fatigue cycles while the electric field is 2038 kV cm À1 are exhibited in Fig. S7 (ESI †).…”

Surface Core-Level Shifts as a Toolbox to Evidence the BaTiO3 Ferroelectric Phase Transition

“…Indeed, in agreement with previous results on CaTiO 3 38 and as it can be observed in Figure 8, the Ti 3d orbitals split into two levels (t 2g , e g ) in the cubic (i.e., paraelectric) structure. On the contrary, in the ferroelectric phase, this degeneracy is lifted due to a change in symmetry from cubic to tetragonal, where orbitals are further split into four sublevels (d xy = d zx , d yz , d z 2 , and d x y 2) for the TiO 2 ones underneath the terminal BaO layer. These modifications in degeneracy in Ti 3d levels observed between ferro-and paraelectric phases and between TiO 2 underneath surface and bulk TiO 2 layers might also be behind the observed splitting of Ba 4d core levels and their variation with temperature and strain.…”

“…In recent years, ferroelectric materials have gained a lot of attention due to their promising use in many technological applications such as nonvolatile memory devices, capacitors, or photocatalysts. , Barium titanate (BaTiO 3 ) is a prototypical ferroelectric; it was the first ceramic material discovered exhibiting ferroelectricity . At room temperature, BaTiO 3 has a tetragonal P 4 mm structure where the Ba 2+ ions are at the corners, the O 2– ions at the center of the faces, and the Ti 4+ ion at the body center.…”

Multifunctional Flexible Ferroelectric Thin Films with Large Electrocaloric Effect and High Energy Storage Performance

“…Our previous study has proved that doping BaTiO 3 (BTO) into BMT could form solid solutions, which possess excellent relaxor properties. 21 In this work, we further explore the EC effect and energy storage properties of the 0.75 Bi(Mg 0.5 Ti 0.5 )O 3 −0.25 BaTiO 3 (BMT−BTO) thin film with 1.5 mol % of Mn doping. The two-dimensional mica is selected as the substrate to fabricate multifunctional flexible ferroelectric devices.…”