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Abstract Relaxor ferroelectrics (RFEs) are being actively investigated for energy‐storage applications due to their large electric‐field‐induced polarization with slim hysteresis and fast energy charging–discharging capability. Here, a novel nanograin engineering approach based upon high kinetic energy deposition is reported, for mechanically inducing the RFE behavior in a normal ferroelectric Pb(Zr0.52Ti0.48)O3(PZT), which results in simultaneous enhancement in the dielectric breakdown strength (EDBS) and polarization. Mechanically transformed relaxor thick films with 4 µm thickness exhibit an exceptionalEDBSof 540 MV m−1and reduced hysteresis with large unsaturated polarization (103.6 µC cm−2), resulting in a record high energy‐storage density of 124.1 J cm−3and a power density of 64.5 MW cm−3. This fundamental advancement is correlated with the generalized nanostructure design that comprises nanocrystalline phases embedded within the amorphous matrix. Microstructure‐tailored ferroelectric behavior overcomes the limitations imposed by traditional compositional design methods and provides a feasible pathway for realization of high‐performance energy‐storage materials.
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Ultrahigh capacitive energy density in ion-bombarded relaxor ferroelectric films
Dielectric capacitors can store and release electric energy at ultrafast rates and are extensively studied for applications in electronics and electric power systems. Among various candidates, thin films based on relaxor ferroelectrics, a special kind of ferroelectric with nanometer-sized domains, have attracted special attention because of their high energy densities and efficiencies. We show that high-energy ion bombardment improves the energy storage performance of relaxor ferroelectric thin films. Intrinsic point defects created by ion bombardment reduce leakage, delay low-field polarization saturation, enhance high-field polarizability, and improve breakdown strength. We demonstrate energy storage densities as high as ~133 joules per cubic centimeter with efficiencies exceeding 75%. Deterministic control of defects by means of postsynthesis processing methods such as ion bombardment can be used to overcome the trade-off between high polarizability and breakdown strength.
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- Award ID(s):
- 1708615
- PAR ID:
- 10167803
- Publisher / Repository:
- American Association for the Advancement of Science (AAAS)
- Date Published:
- Journal Name:
- Science
- Volume:
- 369
- Issue:
- 6499
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- p. 81-84
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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