Abstract
Chemical design of lead-free relaxors with simultaneously high energy density (Wrec) and high efficiency (η) for capacitive energy-storage has been a big challenge for advanced electronic systems. The current situation indicates that realizing such superior energy-storage properties requires highly complex chemical components. Herein, we demonstrate that, via local structure design, an ultrahigh Wrec of 10.1 J/cm3, concurrent with a high η of 90%, as well as excellent thermal and frequency stabilities can be achieved in a relaxor with a very simple chemical composition. By introducing 6s2 lone pair stereochemical active Bi into the classical BaTiO3 ferroelectric to generate a mismatch between A- and B-site polar displacements, a relaxor state with strong local polar fluctuations can be formed. Through advanced atomic-resolution displacement mapping and 3D reconstructing the nanoscale structure from neutron/X-ray total scattering, it is revealed that the localized Bi enhances the polar length largely at several perovskite unit cells and disrupts the long-range coherent Ti polar displacements, resulting in a slush-like structure with extremely small size polar clusters and strong local polar fluctuations. This favorable relaxor state exhibits substantially enhanced polarization, and minimized hysteresis at a high breakdown strength. This work offers a feasible avenue to chemically design new relaxors with a simple composition for high-performance capacitive energy-storage.
| Original language | English |
|---|---|
| Pages (from-to) | 6194-6202 |
| Number of pages | 9 |
| Journal | Journal of the American Chemical Society |
| Volume | 145 |
| Issue number | 11 |
| DOIs | |
| State | Published - Mar 22 2023 |
Funding
This work was supported by the National Natural Science Foundation of China (Grant Nos. 22235002 and 22075014), the Fundamental Research Funds for the Central Universities, China (Grant No. 06500162), and the China Postdoctoral Science Foundation (BX20200044 and 2020M680344). A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The use of the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. This work was supported by the National Natural Science Foundation of China (22175117), the China Postdoctoral Science Foundation (2020M681343 and 2021T140462), and the Science and Technology Commission of Shanghai Municipality (19YF1433300). This work was partially supported by ShanghaiTech University Startup Fund and Double First-Class Initiative Fund of ShanghaiTech University. The authors also appreciate the support from the Shanghai Key Laboratory of High-resolution Electron Microscopy (Shanghai Science and Technology Plan, 21DZ2260400) and the Centre for High-Resolution Electron Microscopy (CℏEM) (No. EM02161943), School of Physical Science and Technology of ShanghaiTech University.