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Title: Ultrahigh–energy density lead-free dielectric films via polymorphic nanodomain design
Dielectric capacitors with ultrahigh power densities are fundamental energy storage components in electrical and electronic systems. However, a long-standing challenge is improving their energy densities. We report dielectrics with ultrahigh energy densities designed with polymorphic nanodomains. Guided by phase-field simulations, we conceived and synthesized lead-free BiFeO 3 -BaTiO 3 -SrTiO 3 solid-solution films to realize the coexistence of rhombohedral and tetragonal nanodomains embedded in a cubic matrix. We obtained minimized hysteresis while maintaining high polarization and achieved a high energy density of 112 joules per cubic centimeter with a high energy efficiency of ~80%. This approach should be generalizable for designing high-performance dielectrics and other functional materials that benefit from nanoscale domain structure manipulation.  more » « less
Award ID(s):
1744213
NSF-PAR ID:
10123055
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
365
Issue:
6453
ISSN:
0036-8075
Page Range / eLocation ID:
578 to 582
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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