Gold nanorods doping induced performance improvement of room temperature OTFT NO2sensors

Sihui Hou; Bingyao Shao; Xinge Yu; Junsheng Yu

doi:10.1088/1361-6528/abfe90

Gold nanorods doping induced performance improvement of room temperature OTFT NO₂sensors

Nanotechnology. 2021 May 21;32(32). doi: 10.1088/1361-6528/abfe90.

Authors

Sihui Hou¹, Bingyao Shao¹, Xinge Yu², Junsheng Yu¹

Affiliations

¹ State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China (UESTC), Chengdu, 610054, People's Republic of China.
² Department of Biomedical Engineering, City University of Hong Kong, Hong Kong, People's Republic of China.

PMID: 33957611
DOI: 10.1088/1361-6528/abfe90

Abstract

Solution-processed organic thin-film transistors (OTFTs) are regarded as the promising candidates for low-cost gas sensors due to their advantages of high throughput, large-area and sensitive to various gas analytes. Microstructure control of organic active layers in OTFTs is an effective route to improve the sensing performance. In this work, we report a simple method to modify the morphology of 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) thin films via doping gold nanorods (Au NRs) for enhancing the performance of the corresponding OTFT sensors for nitrogen dioxide (NO₂) detection. With the optimized doping ratio of Au nanorods, the TIPS-pentacene OTFT snesors not only exhibit a 3-fold increase in mobility, but also obtain a high sensitivity of 70% to 18 ppm NO₂with a detection limit of 270 ppb. The microstructures and morphologies of the modified TIPS-pentacene thin film characterized by atomic force microscopy and field scanning electron microscope. The experimental results indicate that the proper addition of Au NRs could effectively regulate the grain size of TIPS-pentacene, and therein control the density of grain boundaries during the crystallization, which is essential for the high-performance gas sensors.

Keywords: gas sensor; gold nanorods; nitrogen dioxide; organic thin-film transistors.