Grain Boundary Control of Organic Semiconductors via Solvent Vapor Annealing for High-Sensitivity NO2 Detection

Sihui Hou; Xinming Zhuang; Huidong Fan; Junsheng Yu

doi:10.3390/s21010226

Grain Boundary Control of Organic Semiconductors via Solvent Vapor Annealing for High-Sensitivity NO₂ Detection

Sensors (Basel). 2021 Jan 1;21(1):226. doi: 10.3390/s21010226.

Authors

Sihui Hou¹, Xinming Zhuang¹, Huidong Fan¹, Junsheng Yu¹

Affiliation

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, China.

Abstract

The microstructure of the organic semiconductor (OSC) active layer is one of the crucial topics to improve the sensing performance of gas sensors. Herein, we introduce a simple solvent vapor annealing (SVA) process to control 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) OSC films morphology and thus yields high-sensitivity nitrogen organic thin-film transistor (OTFT)-based nitrogen dioxide (NO₂) sensors. Compared to pristine devices, the toluene SVA-treated devices exhibit an order of magnitude responsivity enhancement to 10 ppm NO₂, further with a limit of detection of 148 ppb. Systematic studies on the microstructure of the TIPS-pentacene films reveal the large density grain boundaries formed by the SVA process, improving the capability for the adsorption of gas molecules, thus causing high-sensitivity to NO₂. This simple SVA processing strategy provides an effective and reliable access for realizing high-sensitivity OTFT NO₂ sensors.

Keywords: gas sensors; grain boundary; nitrogen dioxide; organic thin-film transistors; solvent vapor annealing.

Publication types

Letter

Abstract

Publication types

Grants and funding