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Nano Research 2023, 16(9): 11885-11892 https://doi.org/10.1007/s12274-023-5722-y
Research Article | Issue | Published: 29 April 2023

Coaxial fiber organic electrochemical transistor with high transconductance

Show Author's Information Yuan Fang,  Jianyou Feng,  Xiang Shi,  Yiqing Yang,  Jiajia Wang,  Xiao Sun,  Wenjun Li,  Xuemei Sun( ),  Huisheng Peng( )
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China
Keywords:
fiber, hydrogen peroxide, glucose, coaxial structure, ascorbic acid, organic electrochemical transistor
Topics:
Chemical sensors
Cite this article:
Fang Y, Feng J, Shi X, et al. Coaxial fiber organic electrochemical transistor with high transconductance. Nano Research, 2023, 16(9): 11885-11892. https://doi.org/10.1007/s12274-023-5722-y
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Abstract Full text Electronic supplementary material About this article

Fiber organic electrochemical transistors (OECTs) have received extensive attention in wearable and implantable biosensors because of their high flexibility and low working voltage. However, the transconductance of fiber OECTs is much lower compared with the planar counterparts, leading to low sensitivity. Here, we developed fiber OECTs in a coaxial configuration with microscale channel length to achieve the highest transconductance of 135 mS, which is one to two orders of magnitude higher than that of the state-of-the-art fiber OECTs. Coaxial fiber OECT based sensors showed high sensitivities of 12.78, 20.53 and 3.78 mA/decade to ascorbic acid, hydrogen peroxide and glucose, respectively. These fiber OECTs were woven into a fabric to monitor the glucose in sweat during exercise and implanted in mouse brain to detect ascorbic acid. This coaxial architectural design offers an effective way to promote the performance of fiber OECTs and realize highly sensitive detection of biochemicals.


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About this article

Coaxial fiber organic electrochemical transistor with high transconductance

Show Author's information Yuan Fang, Jianyou Feng, Xiang Shi, Yiqing Yang, Jiajia Wang, Xiao Sun, Wenjun Li, Xuemei Sun( ), Huisheng Peng( )
State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China

Abstract

Fiber organic electrochemical transistors (OECTs) have received extensive attention in wearable and implantable biosensors because of their high flexibility and low working voltage. However, the transconductance of fiber OECTs is much lower compared with the planar counterparts, leading to low sensitivity. Here, we developed fiber OECTs in a coaxial configuration with microscale channel length to achieve the highest transconductance of 135 mS, which is one to two orders of magnitude higher than that of the state-of-the-art fiber OECTs. Coaxial fiber OECT based sensors showed high sensitivities of 12.78, 20.53 and 3.78 mA/decade to ascorbic acid, hydrogen peroxide and glucose, respectively. These fiber OECTs were woven into a fabric to monitor the glucose in sweat during exercise and implanted in mouse brain to detect ascorbic acid. This coaxial architectural design offers an effective way to promote the performance of fiber OECTs and realize highly sensitive detection of biochemicals.

Keywords: fiber, hydrogen peroxide, glucose, coaxial structure, ascorbic acid, organic electrochemical transistor

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Publication history
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Acknowledgements

Publication history

Received: 31 January 2023
Revised: 14 March 2023
Accepted: 09 April 2023
Published: 29 April 2023
Issue date: September 2023

Copyright

© Tsinghua University Press 2023

Acknowledgements

Acknowledgements

This work was supported by the National Natural Science Foundation of China (NSFC, Nos. 52122310 and 22075050), Science and Technology Commission of Shanghai Municipality (STCSM, Nos. 21511104900 and 20JC1414902), China Postdoctoral Science Foundation (CPSF, Nos. VLH1717003, KLH1717015), Shanghai Municipal Science and Technology Major Project (No. 2018SHZDZX01), ZJ Lab, and Shanghai Center for Brain Science and Brain-Inspired Technology.

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