Negatively Charged Nanosheets Significantly Enhance the Energy-Storage Capability of Polymer-Based Nanocomposites

Zhiwei Bao; Chuangming Hou; Zhonghui Shen; Haoyang Sun; Genqiang Zhang; Zhen Luo; Zhizhan Dai; Chengming Wang; Xiaowei Chen; Liangbin Li; Yuewei Yin; Yang Shen; Xiaoguang Li

doi:10.1002/adma.201907227

Negatively Charged Nanosheets Significantly Enhance the Energy-Storage Capability of Polymer-Based Nanocomposites

Adv Mater. 2020 Jun;32(25):e1907227. doi: 10.1002/adma.201907227. Epub 2020 May 13.

Authors

Zhiwei Bao¹, Chuangming Hou¹, Zhonghui Shen², Haoyang Sun¹, Genqiang Zhang³, Zhen Luo¹, Zhizhan Dai¹, Chengming Wang¹, Xiaowei Chen⁴, Liangbin Li⁴, Yuewei Yin¹, Yang Shen², Xiaoguang Li^{1

5}

Affiliations

¹ Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics and CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, University of Science and Technology of China, Hefei, 230026, P. R. China.
² School of Materials Science and Engineering, State Key Lab of New Ceramics and Fine Processing, Tsinghua University, Beijing, 100084, P. R. China.
³ CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, 230026, P. R. China.
⁴ National Synchrotron Radiation Lab, CAS Key Laboratory of Soft Matter Chemistry, University of Science and Technology of China, Hefei, 230026, P. R. China.
⁵ Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, P. R. China.

PMID: 32402131
DOI: 10.1002/adma.201907227

Abstract

Polymer-based dielectric materials play a key role in advanced electronic devices and electric power systems. Although extensive research has been devoted to improve their energy-storage performances, it is a great challenge to increase the breakdown strength of polymer nanocomposites in terms of achieving high energy density and good reliability under high voltages. Here, a general strategy is proposed to significantly improve their breakdown strength and energy storage by adding negatively charged Ca₂ Nb₃ O₁₀ nanosheets. A dramatically enhanced breakdown strength (792 MV m^-1 ) and the highest energy density (36.2 J cm^-3 ) among all flexible polymer-based dielectrics are observed in poly(vinylidene fluoride)-based nanocomposite capacitors. The strategy generalizability is verified by the similar substantial enhancements of breakdown strength and energy density in polystyrene-based nanocomposites. Phase-field simulations demonstrate that the further enhanced breakdown strength is ascribed to the local electric field, produced by the negatively charged Ca₂ Nb₃ O₁₀ nanosheets sandwiched with the positively charged polyethyleneimine, which suppresses the secondary impact-ionized electrons and blocks the breakdown path in nanocomposites. The results demonstrate a new horizon of high-energy-density flexible capacitors.

Keywords: breakdown strength; dielectric nanocomposites; energy storage; nanosheets.

Abstract

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