Ultrahigh Energy Storage Density in Glassy Ferroelectric Thin Films under Low Electric Field

Abstract

The current approach to achieving superior energy storage density in dielectrics is to increase their breakdown strength, which often incurs heat generation and unexpected insulation failures, greatly deteriorating the stability and lifetime of devices. Here, a strategy is proposed for enhancing recoverable energy storage density (Wr) while maintaining a high energy storage efficiency (η) in glassy ferroelectrics by creating super tetragonal (super‐T) nanostructures around morphotropic phase boundary (MPB) rather than exploiting the intensely strong electric fields. Accordingly, a giant Wr of ≈86 J cm−3 concomitant with a high η of ≈81% is acquired under a moderate electric field (1.7 MV cm−1) in thin films having MPB composition, namely, 0.94(Bi, Na)TiO3‐0.06BaTiO3 (BNBT), where the local super‐T polar clusters (tetragonality ≈1.25) are stabilized by interphase strain. To the knowledge of the authors, the Wr of the engineered BNBT thin films represents a new record among all the oxide perovskites under a similar strength of electric field to date. The phase field simulation results ascertain that the improved Wr is attributed to the local strain heterogeneity and the large spontaneous polarization primarily is originated from the super‐T polar clusters. The findings in this work present a genuine opportunity to develop ultrahigh‐energy‐density thin‐film capacitors for low‐electric‐field‐driven nano/microelectronics.

Enhanced Absolute Recovered Energy under Low Electric Field in All‐Inorganic 0–3 Nanocomposition Thick Films

“…This means that the driving voltage for polymer nanocomposite thick films is over 10 4 −10 5 V to achieve high energy-storage performances, which presents a great challenge to the supporting insulation systems in electronic devices, limiting the applications of miniaturized devices with a high level of integration. [12] A low-to-moderate electric field is often preferred for dielectric energy storage, which can reduce the probability of breakdown and benefit the operation reliability and cycling lifetime of the device. It should be pointed out that the present achievable energy density in this work far outperforms all the reported dielectric polymer nanocomposites under identical electric field ranges whose energy density is over 14.62 J cm −3 , especially at low electric fields of ≈1100 kV cm −1 .…”

“…Such a high electric field concerns corona leakage, Joule heating, electrical fatigue, and catastrophic dielectric breakdown, which throws a great challenge to the reliability of the electronic device. [12] From an industrialization perspective, achieving comparable energy density under finite electric field strength (preferably below 1000 kV cm −1 ) is the best solution for successfully deploying envisaged energy storage systems in current pulsed power circuits. [13,14] It is practically more feasible to fabricate energy storage capacitors by employing inorganic ceramic thick films with strong durability and reliability because their high 𝜖 r enables them to store large amounts of energy at low electric fields.…”

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

“…6(e). 22,32,33,[35][36][37][38][39][40] (PbLa)ZrO 3 films exhibit excellent energy storage performance by designing nanocrystalline microstructures. With excellent W rec and Z, as well as a high E b , our results have promising prospects in the field of highperformance dielectric capacitors.…”

Ultrahigh Energy Density of Antiferroelectric PbZrO3‐Based Films at Low Electric Field

“…It is important to mention that for wearable and portable devices, including micro-robots, health monitoring sensor as well as micro-electromechanical systems (MEMS), high performances at low electric field/voltage (≈1 MV cm −1 or <10 2 V) are essential requirement, due to the limitations of power supply and the need for compact and lightweight design. [13][14][15][16] This necessitates the use of dielectric materials that can operate effectively at low driving electric field without compromising their performance.…”