Two-dimensional black phosphorus/tin oxide heterojunctions for high-performance chemiresistive H2S sensing

Yong Zhou; Zhihao Hu; Hongchao Zhao; Yanjie Wang; Jing Li; Cheng Zou

doi:10.1016/j.aca.2023.340825

Two-dimensional black phosphorus/tin oxide heterojunctions for high-performance chemiresistive H₂S sensing

Anal Chim Acta. 2023 Mar 8:1245:340825. doi: 10.1016/j.aca.2023.340825. Epub 2023 Jan 12.

Authors

Yong Zhou¹, Zhihao Hu², Hongchao Zhao², Yanjie Wang², Jing Li², Cheng Zou³

Affiliations

¹ Key Laboratory of Optoelectronic Technology and System of Ministry of Education, College of Optoelectronic Engineering, Chongqing University, Chongqing, 400044, People's Republic of China. Electronic address: zhyf@cqu.edu.cn.
² Key Laboratory of Optoelectronic Technology and System of Ministry of Education, College of Optoelectronic Engineering, Chongqing University, Chongqing, 400044, People's Republic of China.
³ Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, Innovative Drug Research Center, School of Pharmaceutical Sciences, Chongqing University, Chongqing, 401331, People's Republic of China. Electronic address: zouchengidrc@cqu.edu.cn.

PMID: 36737130
DOI: 10.1016/j.aca.2023.340825

Abstract

Hydrogen sulfide (H₂S) emission from industrial fields and bacteria decomposing of sulfur-containing organic matter poses a significant impact on human health and atmospheric environment, thus necessitating the development of a H₂S sensor with high sensitivity and exclusive selectivity especially at a very low dose. Chemiresistive sensors based on traditional metal oxides were readily limited by the elevated operating temperature and severe cross-sensitivity. To overcome these obstacles, we prepared two dimensional (2D) tin oxide (SnO₂) nanosheets decorated with thin black phosphorus (BP) as the sensing layer of MEMS H₂S sensors. Compared with pure SnO₂ counterparts, BP-SnO₂ sensors demonstrated lower optimal working temperature (130 °C vs. 160 °C), higher response (8.1 vs. 4.6) and faster response/recovery speeds (39.8 s/47.4 s vs. 79 s/140 s) toward 5 ppm H₂S as well as larger sensitivity (1.3/ppm vs. 0.342/ppm). In addition, favorable repeatability, long-term stability, selectivity and humidity tolerance were exhibited. Thin BP not only served as an excellent conductivity platform within the composites, but enriched the adsorption sites by constructing p-n heterojunctions and introducing more oxygen vacancy, thus separately accelerating and strengthening the gas-solid interaction. This study showcased the application superiorities of BP nanosheets in the field of gas sensing, simultaneously providing a new strategy for trace H₂S sensing via the 2D heterojunctions.

Keywords: Black phosphorus; H(2)S gas sensors; Oxygen vacancy; SnO(2) nanosheets; Two-dimensional heterojunctions.