Topological insulator Bi2Se3 for highly sensitive, selective and anti-humidity gas sensors

• Published in: iScience Vol. 26; no. 4; p. 106387
• Main Authors: Du, Bingsheng, Kang, Wei, He, Yong, Wang, Yan, Yang, Xi, Meng, Gang, Zhu, Zetao, Lin, Xiaohui, Tan, Yiling, Liang, Chengyao, Guo, Xuezheng, Jian, Jikang, Guo, Yongcai, Zhou, Miao
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 21.04.2023; Elsevier
• Subjects: Condensed matter properties; Sensor; Structural property of matter; Structural property of matter; Sensor; Condensed matter properties
• ISSN: 2589-0042; 2589-0042
• DOI: 10.1016/j.isci.2023.106387

Chemiresistive gas sensors generally surfer from low selectivity, inferior anti-humidity, low response signal or signal-to-noise ratio, severely limiting the precise detection of chemical agents. Herein, we exploit high-performance gas sensors based on topological insulator Bi2Se3 that is distinguished from conventional materials by robust metallic surface states protected by time-reversal symmetry. In the presence of Se vacancies, Bi2Se3 nanosheets exhibit excellent gas sensing capability toward NO2, with a high response of 93% for 50 ppm and an ultralow theoretical limit of detection concentration about 0.06 ppb at room temperature. Remarkably, Bi2Se3 demonstrates ultrahigh anti-humidity interference characteristics, as the response with standard deviation of only 3.63% can be achieved in relative humidity range of 0–80%. These findings are supported by first-principles calculations, with analyses on adsorption energy and charge transfer directly revealing the anti-humidity and selectivity. This work may pave the way for implementation of exotic quantum states for intelligent applications. [Display omitted] •Topological insulator Bi2Se3 based high-performance gas sensors are demonstrated•Se vacancies enhance the gas sensing capability of Bi2Se3 toward NO2•The sensing device exhibits ultrahigh anti-humidity interference characteristics•First-principles analyses reveal the mechanism of anti-humidity and selectivity Sensor; Condensed matter properties; Structural property of matter