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Research Article

N-doped MoS2 via assembly transfer on an elastomeric substrate for high-photoresponsivity, air-stable and stretchable photodetector

Shuyan Qi1,§, Weifeng Zhang1,§, Xiaoli Wang1, Yifan Ding2, Yan Zhang1, Jiakang Qiu1, Ting Lei3, Run Long1, Nan Liu1( )
Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875, China
Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center of Soft Matter Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China

§ Shuyan Qi and Weifeng Zhang contributed equally to this work.

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Graphical Abstract

Current work combines single-layer MoS2 with electron-rich N-DMBI and transfers microelectronic devices assembly onto SEBS elastomer to fabricate high-performance (R > 700 A·W−1, D* > 1 × 1011 J), air-stable and stretchable photodetectors.

Abstract

As a direct-bandgap semiconductor, single-layer MoS2 has gained great attention in optoelectronics, especially wearable photodetectors. However, MoS2 exhibits poor photoresponsivity on a stretchable substrate due to intrinsic low carrier density and a large number of scattering centers on polymer substrates. Few air-stable yet strong dopants on MoS2 has been reported. In addition, the roughness, hydrophobicity and susceptibility to organic solvents of polymer surface are critical roadblocks in the development of stretchable high-performance MoS2 photodetectors. Here, we realize a stretchable and stable photodetector with high photoresponsivity by combining n-type dopant ((4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl) phenyl) dimethylamine, N-DMBI) with MoS2 and assembly transfer technique. It is found electron tends to transfer from N-DMBI to MoS2 and the effect is maintained after the integrable photodetector transferred directly by elastic substrate styrene-ethylene-butylene-styrene (SEBS), even after being exposed to the air for 20 days, which benifits greatly from the encapsulation of SEBS. The increased carrier density greatly promotes carrier injection efficiency and photogenerated electron–hole separation efficiency at the metal–semiconductor interface, thus offering a significantly improved photoresponsivity in MoS2 photodetectors. Moreover, such photodetector shows great durability to stretch, which can remain functional after stretched 100 cycles within its stretch limit. Our strategy opens a new avenue to fabricate high-photoresponsivity stretchable electronics or optoelectronics of two-dimensional (2D) materials.

Keywords

transition metal dichalcogenidescharge transferstretchable photodetectorsorganic molecules

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Nano Research
Volume 15 Issue 11,
November 2022
Pages 9866-9874
DOI: 10.1007/s12274-022-4146-4
Cite this article:
Qi S, Zhang W, Wang X, et al. N-doped MoS2 via assembly transfer on an elastomeric substrate for high-photoresponsivity, air-stable and stretchable photodetector. Nano Research, 2022, 15(11): 9866-9874. https://doi.org/10.1007/s12274-022-4146-4
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Received: 01 October 2021
Revised: 07 January 2022
Accepted: 11 January 2022
Published: 27 February 2022
© Tsinghua University Press 2022
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