Fu Jian, Xie Aiwen, Zuo Ruzhong, Liu Yiqian, Qi He, Wang Zongqian, Feng Quan, Guo Jinming, Zeng Kun, Chen Xuefeng, Fu Zhengqian, Zhang Yifan, Jiang Xuewen, Li Tianyu, Zhang Shujun, Lin Yuan-Hua, Nan Ce-Wen
School of Materials Science and Engineering, Hefei University of Technology, Hefei, China.
Center for Advanced Ceramics, School of Materials Science and Engineering, Anhui Polytechnic University, Wuhu, China.
Nat Commun. 2024 Aug 26;15(1):7338. doi: 10.1038/s41467-024-51766-z.
Relaxor ferroelectrics are highly desired for pulse-power dielectric capacitors, however it has become a bottleneck that substantial enhancements of energy density generally sacrifice energy efficiency under superhigh fields. Here, we demonstrate a novel concept of highly polarizable concentrated dipole glass in delicately-designed high-entropy (BiBaNa)(FeTiNb)O ceramic achieved via substitution of multiple heterovalent ferroelectric-active principal cation species on equivalent lattice sites. The atomic-scaled polar heterogeneity of dipoles with different polar vectors between adjacent unit cells enables diffuse reorientation process but disables appreciable growth with electric fields. These unique features cause superior recoverable energy density of ~15.9 J cm and efficiency of ~93.3% in bulk ceramics. We also extend the highly polarizable concentrated dipole glass to the prototype multilayer ceramic capacitor, which exhibits record-breaking recoverable energy density of ~26.3 J cm and efficiency of ~92.4% with excellent temperature and cycle stability. This research presents a distinctive approach for designing high-performance energy-storage dielectric capacitors.
弛豫铁电体是脉冲功率介电电容器的理想材料，然而，在超高场下，能量密度的大幅提高通常会牺牲能量效率，这已成为一个瓶颈。在此，我们展示了一种在精心设计的高熵（BiBaNa）（FeTiNb）O陶瓷中实现的高极化集中偶极玻璃的新概念，该陶瓷是通过在等效晶格位置上取代多种异价铁电活性主阳离子物种而制成的。相邻晶胞之间具有不同极矢量的偶极子在原子尺度上的极性不均匀性使得偶极子能够进行扩散重取向过程，但不会随着电场而显著增长。这些独特的特性使得块状陶瓷具有约15.9 J/cm³的优异可恢复能量密度和约93.3%的效率。我们还将高极化集中偶极玻璃扩展到原型多层陶瓷电容器，该电容器具有破纪录的约26.3 J/cm³的可恢复能量密度和约92.4%的效率，以及出色的温度和循环稳定性。这项研究提出了一种设计高性能储能介电电容器的独特方法。
