Cold Sintering Preparation and Dielectric Properties of 0-3 Type Barium Strontium Titanate/Polytetrafluoroethylene Composites

Abstract

Abstract: 0-3 type barium strontium titanate (BST)/polytetrafluoroethylene (PTFE) composites are new types of ceramic/polymer functional composites. They combine advantages of BST ceramic and PTFE polymer, and show high dielectric constant and dielectric adjustability. However, due to the low dielectric constant of polymer phase, the dielectric constant of composites with polymer as matrix and ceramic as filling phase prepared by conventional methods such as flow casting method is basically below 100. In order to further improve the dielectric properties of BST/PTFE composites, a new sintering process (cold sintering process) was used to realize the co-sintering of BST ceramic and PTFE polymer. In the experiment, 0-3 type BST/PTFE composites were prepared by introducing PTFE with a volume ratio of 5% into BST matrix, and solid barium hydroxide octahydrate (Ba(OH)₂·8H₂O) as transient liquid phase to assist the sintering process. The dielectric properties of the composites under different cold sintering conditions were investigated. The results show that the dielectric constant of the composite samples reach more than 500 (25 ℃, 1 kHz) under the conditions of cold sintering temperature of 275 ℃, pressure of 200 MPa and time of 2.5 h. Compared with the conventional preparation process, the dielectric constant of the composites prepared by cold sintering process has been greatly improved, which has a certain reference significance for the low-temperature preparation and research of ceramic/polymer functional composites.

Key words: barium strontium titanate, polytetrafluoroethylene, Ba(OH)₂·8H₂O, cold sintering, micro morphology, dielectric property

CLC Number:

TB332

YING Xiaoyun, LIU Jun, QIAO Wenhao, ZHOU Ming, LUO Ying. Cold Sintering Preparation and Dielectric Properties of 0-3 Type Barium Strontium Titanate/Polytetrafluoroethylene Composites[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(7): 2574-2583.

References

[1] YU Y, WANG X S, YAO X. Dielectric properties of Ba_1-xSr_xTiO₃ ceramics prepared by microwave sintering[J]. Ceramics International, 2013, 39: S335-S339.
[2] HUANG Y H, WU Y J, LI J, et al. Enhanced energy storage properties of Barium strontium titanate ceramics prepared by sol-gel method and spark plasma sintering[J]. Journal of Alloys and Compounds, 2017, 701: 439-446.
[3] YU M, GRASSO S, MCKINNON R, et al. Review of flash sintering: materials, mechanisms and modelling[J]. Advances in Applied Ceramics, 2017, 116(1): 24-60.
[4] ANDREWS J, BUTTON D, REANEY I M. Advances in cold sintering: improving energy consumption and unlocking new potential in component manufacturing[J]. Johnson Matthey Technology Review, 2020, 64(2): 219-232.
[5] GRASSO S, BIESUZ M, ZOLI L, et al. A review of cold sintering processes[J]. Advances in Applied Ceramics, 2020, 119(3): 115-143.
[6] GUO J, FLOYD R, LOWUM S, et al. Cold sintering: progress, challenges, and future opportunities[J]. Annual Review of Materials Research, 2019, 49: 275-295.
[7] GUO J, GUO H Z, BAKER A L, et al. Cold sintering: a paradigm shift for processing and integration of ceramics[J]. Angewandte Chemie International Edition, 2016, 55(38): 11457-11461.
[8] SADA T K, TSUJI K, NDAYISHIMIYE A, et al. High permittivity BaTiO₃ and BaTiO₃-polymer nanocomposites enabled by cold sintering with a new transient chemistry: Ba(OH)₂·8H₂O[J]. Journal of the European Ceramic Society, 2021, 41(1): 409-417.
[9] JING Y, LUO N N, WU S H, et al. Remarkably improved electrical conductivity of ZnO ceramics by cold sintering and post-heat-treatment[J]. Ceramics International, 2018, 44(16): 20570-20574.
[10] WANG D X, TSUJI K, RANDALL C A, et al. Model for the cold sintering of lead zirconate titanate ceramic composites[J]. Journal of the American Ceramic Society, 2020, 103(9): 4894-4902.
[11] SEO J H, FAN Z M, NAKAYA H, et al. Cold sintering, enabling a route to co-sinter an all-solid-state lithium-ion battery[J]. Japanese Journal of Applied Physics, 2021, 60(3): 037001.
[12] CHEN M H, YIN J H, FENG Y, et al. Effect of content on dielectric performance of barium titanate/polyimide films[C]//Proceedings of 2011 International Conference on Electronic & Mechanical Engineering and Information Technology. August 12-14, 2011, Harbin, China. IEEE, 2011: 2033-2036.
[13] GUO J, ZHAO X T, HERISSON DE BEAUVOIR T, et al. Recent progress in applications of the cold sintering process for ceramic-polymer composites[J]. Advanced Functional Materials, 2018, 28(39): 1801724.
[14] ZHANG Q Q, GAO F, HU G X, et al. Characterization and dielectric properties of modified Ba_0.6Sr_0.4TiO₃/poly(vinylidene fluoride) composites with high dielectric tunability[J]. Composites Science and Technology, 2015, 118: 94-100.
[15] GUO Y T, MENG N, ZHANG Y M, et al. Characterization and performance of plate-like Ba_0.6Sr_0.4TiO₃/poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) composites with high permittivity and low loss[J]. Polymer, 2020, 203: 122777.
[16] GUO Y T, ZHANG K N, MENG N, et al. Microstructure and dielectric properties of sub-micron hollow sphere (Ba_0.6Sr_0.4)TiO₃/PVDF composites[J]. IET Nanodielectrics, 2019, 2(4): 135-141.
[17] XIA W M, XU Z, WEN F, et al. Electrical energy density and dielectric properties of poly(vinylidene fluoride-chlorotrifluoroethylene)/BaSrTiO₃ nanocomposites[J]. Ceramics International, 2012, 38(2): 1071-1075.
[18] GUPTA P, KUMAR A, TOMAR M, et al. Enhanced dielectric properties and suppressed leakage current density of PVDF composites flexible film through small loading of submicron Ba_0.7Sr_0.3TiO₃ crystallites[J]. Journal of Materials Science: Materials in Electronics, 2017, 28(16): 11806-11812.
[19] SADA T K, TSUJI K, NDAYISHIMIYE A, et al. Enhanced high permittivity BaTiO₃-polymer nanocomposites from the cold sintering process[J]. Journal of Applied Physics, 2020, 128(8): 084103.