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This content will become publicly available on April 19, 2025

Title: High energy density in artificial heterostructures through relaxation time modulation
Electrostatic capacitors are foundational components of advanced electronics and high-power electrical systems owing to their ultrafast charging-discharging capability. Ferroelectric materials offer high maximum polarization, but high remnant polarization has hindered their effective deployment in energy storage applications. Previous methodologies have encountered problems because of the deteriorated crystallinity of the ferroelectric materials. We introduce an approach to control the relaxation time using two-dimensional (2D) materials while minimizing energy loss by using 2D/3D/2D heterostructures and preserving the crystallinity of ferroelectric 3D materials. Using this approach, we were able to achieve an energy density of 191.7 joules per cubic centimeter with an efficiency greater than 90%. This precise control over relaxation time holds promise for a wide array of applications and has the potential to accelerate the development of highly efficient energy storage systems.  more » « less
Award ID(s):
2145797 2122070
PAR ID:
10510552
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
Science AAAS
Date Published:
Journal Name:
Science
Volume:
384
Issue:
6693
ISSN:
0036-8075
Page Range / eLocation ID:
312 to 317
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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