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Nano Research 2022, 15(8): 7476-7483 https://doi.org/10.1007/s12274-022-4356-9
Research Article | Issue | Published: 31 May 2022

Highly impermeable and flexible silica encapsulation films synthesized by sol–gel process

Show Author's Information Si-Hoon Kim1,2,  Gyeong-Seok Hwang2,  Donghwan Koo2,  Dong-Hyun Seo1,  Ye-Pil Kwon1,  Hansuek Lee3,  Hyesung Park2,4( ),  Eun-chae Jeon1( ),  Ju-Young Kim2,4( )
School of Materials Science and Engineering, University of Ulsan, Techno saneop-ro 55beon-gil 12, Ulsan 44776, Republic of Korea
Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan 44919, Republic of Korea
Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daehak-ro 291, Deajeon 34141, Republic of Korea
Graduate School of Semiconductor Materials and Devices, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan 44919, Republic of Korea
Keywords:
sol–gel, silica thin film, flexible encapsulation, mechanical reliability, flexible organic solar cell
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Kim S-H, Hwang G-S, Koo D, et al. Highly impermeable and flexible silica encapsulation films synthesized by sol–gel process. Nano Research, 2022, 15(8): 7476-7483. https://doi.org/10.1007/s12274-022-4356-9
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Abstract Full text Electronic supplementary material About this article

Silica thin films synthesized sol–gel process are proposed as flexible encapsulation materials. A sol–gel process provides a dense and stable amorphous silica structure, yielding an extremely high elastic deformation limit of 4.9% and extremely low water vapor transmission rate (WVTR) of 2.90 × 10−4 g/(m2∙day) at 60 °C and relative humidity of 85%. The WVTR is not degraded by cyclic bending deformations for the bending radius corresponding to a tensile strain of 3.3% in the silica encapsulation film, implying that the silica thin film is robust against the formation of pinhole-type defects by cyclic bending deformations. Flexible organic solar cells encapsulated with the silica films operate without degradation in power conversion efficiency for 50,000 bending cycles for a bending radius of 6 mm.


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Electronic supplementary material
About this article

Highly impermeable and flexible silica encapsulation films synthesized by sol–gel process

Show Author's information Si-Hoon Kim1,2, Gyeong-Seok Hwang2, Donghwan Koo2, Dong-Hyun Seo1, Ye-Pil Kwon1, Hansuek Lee3, Hyesung Park2,4( ), Eun-chae Jeon1( ), Ju-Young Kim2,4( )
School of Materials Science and Engineering, University of Ulsan, Techno saneop-ro 55beon-gil 12, Ulsan 44776, Republic of Korea
Department of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan 44919, Republic of Korea
Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daehak-ro 291, Deajeon 34141, Republic of Korea
Graduate School of Semiconductor Materials and Devices, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan 44919, Republic of Korea

Abstract

Silica thin films synthesized sol–gel process are proposed as flexible encapsulation materials. A sol–gel process provides a dense and stable amorphous silica structure, yielding an extremely high elastic deformation limit of 4.9% and extremely low water vapor transmission rate (WVTR) of 2.90 × 10−4 g/(m2∙day) at 60 °C and relative humidity of 85%. The WVTR is not degraded by cyclic bending deformations for the bending radius corresponding to a tensile strain of 3.3% in the silica encapsulation film, implying that the silica thin film is robust against the formation of pinhole-type defects by cyclic bending deformations. Flexible organic solar cells encapsulated with the silica films operate without degradation in power conversion efficiency for 50,000 bending cycles for a bending radius of 6 mm.

Keywords: sol–gel, silica thin film, flexible encapsulation, mechanical reliability, flexible organic solar cell

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Publication history
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Acknowledgements

Publication history

Received: 07 February 2022
Revised: 06 March 2022
Accepted: 23 March 2022
Published: 31 May 2022
Issue date: August 2022

Copyright

© Tsinghua University Press 2022

Acknowledgements

Acknowledgements

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2019R1I1A3A01054545), by National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT (MSIT) (Nos. 2020M3H4A1A02084911 and 2019R1A2C1009025).

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