Xue Bai1, He Lv1, Zhuo Liu1, Junkun Chen1, Jue Wang1, Baihe Sun1, Yang Zhang1, Ruihong Wang2, Keying Shi3. 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.
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 (Ra/Rg) to 100 ppm, which is 26.5 times to that of pure SnO2. 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.
The unique properties of heterostructure materials make them become a promising candidate for high-performance room-temperature (RT) n>an class="Chemical">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 (Ra/Rg) to 100 ppm, which is 26.5 times to that of pure SnO2. 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.