Search

Your search keyword '"Lou, Xiaojie"' showing total 567 results
Start Over Author "Lou, Xiaojie"
567 results on '"Lou, Xiaojie"'

2. Tripling energy storage density through order-disorder transition induced polar nanoregions in PbZrO3 thin films by ion implantation

Author

Luo, Yongjian, Wang, Changan, Chen, Chao, Gao, Yuan, Sun, Fei, Li, Caiwen, Yin, Xiaozhe, Luo, Chunlai, Kentsch, Ulrich, Cai, Xiangbin, Bai, Mei, Fan, Zhen, Qin, Minghui, Zeng, Min, Dai, Jiyan, Zhou, Guofu, Lu, Xubing, Lou, Xiaojie, Zhou, Shengqiang, Gao, Xingsen, Chen, Deyang, and Liu, Jun-Ming

Subjects
Condensed Matter - Materials Science
Abstract

Dielectric capacitors are widely used in pulsed power electronic devices due to their ultrahigh power densities and extremely fast charge/discharge speed. To achieve enhanced energy storage density, both maximum polarization (Pmax) and breakdown strength (Eb) need to be improved simultaneously. However, these two key parameters are inversely correlated. In this study, order-disorder transition induced polar nanoregions (PNRs) have been achieved in PbZrO3 thin films by making use of the low-energy ion implantation, enabling us overcome the trade-off between high polarizability and breakdown strength, which leads to the tripling of the energy storage density from 20.5 J/cm3 to 62.3 J/cm3 as well as the great enhancement of breakdown strength. This approach could be extended to other dielectric oxides to improve the energy storage performance, providing a new pathway for tailoring the oxide functionalities.

Published
2022

13. Enhanced energy storage properties of silver niobate antiferroelectric ceramics with A-site Eu3+ substitution and their structural origin.

Author

Shi, Peng, Liu, Jin, Song, Yuechan, Wu, Wenwen, Liu, Lina, Zhou, Xiaobin, Chen, Xiaoming, Lou, Xiaojie, and Liu, Peng

Subjects
ENERGY storage, LEAD-free ceramics, DIELECTRIC materials, POWER resources, POWER density, FERROELECTRIC ceramics, CERAMICS
Abstract

AgNbO3 (AN)-based lead-free antiferroelectric ceramics are widely studied for their use as dielectric capacitor materials. In this study, Eu3+-doped AN ceramics were prepared and the results show that Eu3+ diffused into the AN lattice. The ceramics were formed by M1 and M2 phases coexisting at room temperature, as distinct from the M1 (M: monoclinic) phase of pure AN. Electrical properties and structural characterization showed that the antiferroelectric stability of the ceramics increases with the increase in Eu3+ levels. At room temperature, Ag0.94Eu0.02NbO3 ceramic exhibited a good energy storage density of 5.3 J/cm3 and a high efficiency of 71.9%. When the temperature rises from room temperature to 140 °C, the efficiency of the sample decreases from 80.4% to 67.1% and Wr decreases from 2.1 to 2.0 J/cm3, which indicates that the sample has good temperature stability. The time constant (t0.9) of this sample was less than 60 ns and the power density (PD) was 51.3 MW/cm3, indicating excellent charge–discharge capabilities. This novel ceramic is expected to be used as a new dielectric capacitor material for pulsed power supplies. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

31. Excellent Energy Storage and Photovoltaic Performances in Bi 0.45 Na 0.45 Ba 0.1 TiO 3 -Based Lead-Free Ferroelectricity Thin Film.

Author

Wu, Jianhua, Zhang, Tiantian, Gao, Xing, Ning, Lei, Hu, Yanhua, Lou, Xiaojie, Liu, Yunying, Sun, Ningning, and Li, Yong

Subjects
FERROELECTRIC thin films, DIELECTRIC films, ENERGY storage, THIN films, ENERGY density
Abstract

Inorganic dielectric films have attracted extensive attention in the field of microelectronic and electrical devices because of their wide operating temperature range, small size, and easy integration. Here, we designed and prepared eco-friendly (1-x)Bi0.45Na0.45Ba0.1TiO3-xBi(Mg1/3Nb2/3)O3 multifunctional ferroelectric thin films for energy storage and photovoltaic. The results show that Bi(Mg1/3Nb2/3)O3 can effectively improve the energy storage performance. At x = 0.05, the energy storage density and efficiency are as high as 73.1 J/cm3 and 86.2%, respectively, and can operate stably in a wide temperature range. The breakdown field strength of the thin films increased significantly, and the analysis showed that the addition of Bi(Mg1/3Nb2/3)O3 caused a change in the internal conduction mechanism. At the same time, the generation of polar nanoregions increases the relaxation characteristics, thus improving the energy storage properties. In addition, the thin film material also has excellent ferroelectric photovoltaic properties. This work represents a new design paradigm that can serve as an effective strategy for developing advanced multi-functional materials. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

42. Microstructural Evolution of Charged Defects in the Fatigue Process of Polycrystalline BiFeO3 Thin Films

Author

Ke, Qingqing, Kumar, Amit, Lou, Xiaojie, Feng, Yuan Ping, Zeng, Kaiyang, Cai, Yongqing, and Wang, John

Subjects
Condensed Matter - Materials Science
Abstract

Fatigue failure in ferroelectrics has been intensively investigated in the past few decades. Most of the mechanisms discussed for ferroelectric fatigue have been built on the "hypothesis of variation in charged defects", which however are rarely evidenced by experimental observation. Here, using a combination of complex impedance spectra techniques, piezoresponse force microscopy and first-principles theory, we examine the microscopic evolution and redistribution of charged defects during the electrical cycling in BiFeO3 thin films. The dynamic formation and melting behaviors of oxygen vacancy (VO) order are identified during the fatigue process. It reveals that the isolated VO tend to self-order along grain boundaries to form a planar-aligned structure, which blocks the domain reversals. Upon further electrical cycling, migration of VO within vacancy clusters is accommodated with a lower energy barrier (~0.2 eV) and facilitates the formation of nearby-electrode layer incorporated with highly concentrated VO. The interplay between the macroscopic fatigue and microscopic evolution of charged defects clearly demonstrates the role of ordered VO cluster in the fatigue failure of BiFeO3 thin films.

Published
2014

Catalog

Books, media, physical & digital resources
See catalog results