Ultrahigh-energy density lead-free dielectric films via polymorphic nanodomain design
Ultrahigh-energy density lead-free dielectric films via polymorphic nanodomain design
复制标题
通过多态纳米域设计的超高能量密度无铅介电薄膜
DOI：
10.1126/science.aaw8109
复制
发表时间：
2019-08-09
期刊：
影响因子：
56.9
通讯作者：
Nan, Ce-Wen
中科院分区：
文献类型：
--
作者：
Pan, Hao;Li, Fei;Nan, Ce-Wen
具有高功率密度的介质电容器是电气和电子系统中的基本能量存储元件。然而，一个长期的挑战是提高它们的能量密度。我们报告了用多态性纳米畴设计的具有能量密度的双光子晶体。在相场模拟的指导下，我们构思并合成了无铅的BiFeO 3-BaTiO 3-SrTiO 3固溶体薄膜，实现了菱面体和四面体纳米畴在立方基体中的共存。我们在保持高极化的同时获得了最小化的滞后，并实现了每立方厘米112焦耳的高能量密度，具有类似于80%的高能量效率。这种方法应该是可推广的设计高性能的MEMS和其他功能材料，受益于纳米级域结构的操纵。
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 BiFeO3-BaTiO3-SrTiO3 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 similar to 80%. This approach should be generalizable for designing high-performance dielectrics and other functional materials that benefit from nanoscale domain structure manipulation.