Thin-layered MoS2 nanoflakes vertically grown on SnO2 nanotubes as highly effective room-temperature NO2 gas sensor

Xue Bai; He Lv; Zhuo Liu; Junkun Chen; Jue Wang; Baihe Sun; Yang Zhang; Ruihong Wang; Keying Shi

doi:10.1016/j.jhazmat.2021.125830

Thin-layered MoS₂ nanoflakes vertically grown on SnO₂ nanotubes as highly effective room-temperature NO₂ gas sensor

J Hazard Mater. 2021 Aug 15:416:125830. doi: 10.1016/j.jhazmat.2021.125830. Epub 2021 Apr 7.

Authors

Xue Bai¹, He Lv¹, Zhuo Liu¹, Junkun Chen¹, Jue Wang¹, Baihe Sun¹, Yang Zhang¹, Ruihong Wang², Keying Shi³

Affiliations

¹ Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education. School of Chemistry and Material Science, Heilongjiang University, Harbin 150080, PR China.
² Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education. School of Chemistry and Material Science, Heilongjiang University, Harbin 150080, PR China. Electronic address: wangruihong@hlju.edu.com.
³ Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education. School of Chemistry and Material Science, Heilongjiang University, Harbin 150080, PR China. Electronic address: shikeying2008@163.com.

PMID: 33865111
DOI: 10.1016/j.jhazmat.2021.125830

Abstract

The unique properties of heterostructure materials make them become a promising candidate for high-performance room-temperature (RT) NO₂ sensing. Herein, a p-n heterojunction consisting of two-dimensional (2D) MoS₂ nanoflakes vertically grown on one-dimensional (1D) SnO₂ nanotubes (NTs) was fabricated via electrospinning and subsequent hydrothermal route. The sulfur edge active sites are fully exposed in the MoS₂@SnO₂ heterostructure due to the vertically oriented thin-layered morphology features. Moreover, the interface of p-n heterojunction provides an electronic transfer channel from SnO₂ to MoS₂, which enables MoS₂ act as the generous electron donor involved in NO₂ gas senor detection. As a result, the optimized MoS₂@SnO₂-2 heterostructure presents an impressive sensitivity and selectivity for NO₂ gas detection at RT. The response value is 34.67 (R_a/R_g) to 100 ppm, which is 26.5 times to that of pure SnO_2. It also exhibits a fast response and recovery time (2.2 s, 10.54 s), as well as a low detection limit (10 ppb) and as long as 20 weeks of stability. This simple fabrication of high-performance sensing materials may facilitate the large-scale production of RT NO₂ gas sensors.

Keywords: High sensitivity; P-n heterojunction; Room-temperature NO(2) sensors; Thin-layered MoS(2) nanoflakes; Vertically grown.