Ultrahigh Energy Storage Performance of Flexible BMT‐Based Thin Film Capacitors

Abstract

Ferroelectric thin film capacitors have attracted increasing attention because of their high energy storage density and fast charge–discharge speed, but less attention has been paid to the realization of flexible capacitors for wearable electronics and power systems. In this work, flexible xMn‐BiMg0.5Ti0.7O3 (xMn‐BMT0.7) thin film capacitors with ultrahigh energy storage density and good stability are deposited on mica substrate. The introduction of excess TiO2 with an amorphous structure contributes to the forming of the polar nano regions, resulting in the reduced ferroelectric hysteresis. In order to further improve the energy storage performance, Mn doping increases the polarization by regulating chemical pressure in the lattices and inhibits the valence change of Ti4+. Especially in the 1.5% Mn‐BMT0.7 film capacitor, an ultrahigh energy storage density of 124 J cm‐3 and an outstanding efficiency of 77% are obtained, which is one of the best energy storage performances recorded for ferroelectric capacitors. In addition, the flexible ferroelectric film capacitor also exhibits good thermal stability (25–200 °C), high frequency reliability (500 Hz–10 kHz), excellent electrical (108 cycles), and mechanical (104 cycles) fatigue properties. This work is expected to pave the way for the application of BMT‐based thin film capacitors in flexible energy storage systems.

Simultaneously enhanced energy density and discharge efficiency of (Na0.5Bi0.5)0.7Sr0.3TiO3-La1/3(Ta0.5Nb0.5)O3 lead-free energy storage ceramics via grain inhibition and dielectric peak flattening engineering

“…Lead-free energy storage ceramics have attracted much attention as a result of their large power density, rapid charge/discharge speed and environmental friendliness compared with other materials. 1–5 For most ceramics, a prominent energy storage density ( W ) usually can be achieved under an extremely large electric field. However, a high electric field usually demands severe reliability of the capacitors and will cause large power consumption, which greatly limits the practicability.…”

Synergistic Optimization in a 0.90BaTiO3–0.08Bi(Ni0.5Zr0.5)O3–0.02BiFeO3 Thin Film with High Breakdown Strength and Energy Density

“…In addition, defined as a large spontaneous polarization material, the increase of BF content enhances P max of the material to some extent. Figure compares other systems of ceramic thin-film energy storage materials with this work. ,,,,,− Owing to its large BDS and enhancive polarization, the 0.90BT–0.08BNZ–0.02BF thin film possesses higher W rec of 114.3 J cm –3 and shows great advantages in pulse power applications.…”

“…The energy storage density of thin film materials achieves a W rec of up to 100 J cm –3 in a micro/nanoscale compared with traditional bulk ceramic capacitors. , In general, the BDS, P max (maximum polarization), and P r (remnant polarization) are dominated by the material system, which can be optimized by ion doping and structural modulation . Although crystalline films are confirmed to possess higher P max , the low BDS and reduced η under a high electric field limit their energy storage performance.…”

Flexible Ceramic Film Sensors for Free-Form Devices

“…So far, not only flexible metal electrodes [126], but also oxide-based flexible transparent electrodes such as Sn-doped In 2 O 3 and Gadoped ZnO, have been extensively studied [127][128][129]. Additionally, research on flexible ceramic resistors (e.g., RuO 2 ) [130] and capacitors (e.g., Ba(Zr 0.35 Ti 0.65 )O 3 and Na 0.5 Bi 0.5 TiO 3 -EuTiO 3 ) [131][132][133][134] has been boosted lately by the significant demand from other primary components and new applications. Resistors and capacitors are essential components for any kind of electronic device.…”