Chemical Design of Pb-Free Relaxors for Giant Capacitive Energy Storage

Hui Liu; Zheng Sun; Ji Zhang; Huajie Luo; Qinghua Zhang; Yonghao Yao; Shiqing Deng; He Qi; Jue Liu; Leighanne C Gallington; Joerg C Neuefeind; Jun Chen

doi:10.1021/jacs.3c02811

Chemical Design of Pb-Free Relaxors for Giant Capacitive Energy Storage

J Am Chem Soc. 2023 May 31;145(21):11764-11772. doi: 10.1021/jacs.3c02811. Epub 2023 May 19.

Authors

Hui Liu^{1

2}, Zheng Sun^{1

2}, Ji Zhang³, Huajie Luo^{1

2}, Qinghua Zhang⁴, Yonghao Yao^{1

2}, Shiqing Deng^{1

2}, He Qi^{1

2}, Jue Liu⁵, Leighanne C Gallington⁶, Joerg C Neuefeind⁵, Jun Chen^{1

2

7}

Affiliations

¹ Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing 100083, China.
² Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
³ School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China.
⁴ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
⁵ Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
⁶ X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States.
⁷ Hainan University, Haikou 570228, Hainan Province, China.

PMID: 37205832
DOI: 10.1021/jacs.3c02811

Abstract

Dielectric capacitors have captured substantial attention for advanced electrical and electronic systems. Developing dielectrics with high energy density and high storage efficiency is challenging owing to the high compositional diversity and the lack of general guidelines. Herein, we propose a map that captures the structural distortion (δ) and tolerance factor (t) of perovskites to design Pb-free relaxors with extremely high capacitive energy storage. Our map shows how to select ferroelectric with large δ and paraelectric components to form relaxors with a t value close to 1 and thus obtaining eliminated hysteresis and large polarization under a high electric breakdown. Taking the Bi_0.5Na_0.5TiO₃-based solid solution as an example, we demonstrate that composition-driven predominant order-disorder characteristic of local atomic polar displacements endows the relaxor with a slushlike structure and strong local polar fluctuations at several nanoscale. This leads to a giant recoverable energy density of 13.6 J cm^-3, along with an ultrahigh efficiency of 94%, which is far beyond the current performance boundary reported in Pb-free bulk ceramics. Our work provides a solution through rational chemical design for obtaining Pb-free relaxors with outstanding energy-storage properties.