Mechanically exfoliated MoS2 nanosheets decorated with SnS2 nanoparticles for high-stability gas sensors at room temperature

• Published in: Rare metals Vol. 40; no. 6; pp. 1536 - 1544
• Main Authors: Liu, Jia-Bei, Hu, Jin-Yong, Liu, Can, Tan, Yu-Ming, Peng, Xiang, Zhang, Yong
• Format: Journal Article
• Language: English
• Published: Beijing Nonferrous Metals Society of China 01.06.2021; Springer Nature B.V
• Subjects: Adsorption; Biomaterials; Chemistry and Materials Science; Decoration; Energy; Exfoliation; Gas sensors; Heterojunctions; Materials Engineering; Materials Science; Metallic Materials; Molybdenum disulfide; Nanocomposites; Nanoparticles; Nanoscale Science and Technology; Nanosheets; Nitrogen dioxide; Original Article; Physical Chemistry; Room temperature; Selectivity; Sensors; Surface chemistry; Surface defects; Surface stability; Tin disulfide; Mechanically exfoliated MoS; MoS; NO; sensing properties; SnS; Room-temperature detection; nanocomposites; nanosheets
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-020-01565-4

Due to its unique physical, chemical and surface electronic properties, molybdenum disulfide (MoS 2 ) nanosheets open up a new avenue for nitrogen dioxide (NO 2 ) detection at room temperature. Nevertheless, the gas sensing properties of pure MoS 2 nanosheets are inevitably degenerated by the adsorption of atmospheric oxygen, which results in weak stability for MoS 2 -based gas sensors. Reducing surface defects and constructing heterojunctions may be effective strategies to improve the gas sensing properties of MoS 2 nanosheets. In this work, we design a novel nanocomposite based on MoS 2 nanosheets decorated with tin disulfide (SnS 2 ) nanoparticles (MoS 2 /SnS 2 ) via combining the mechanical exfoliation method with the facile hydrothermal method. The experimental results indicate that, after surfaces decoration with SnS 2 nanoparticles, the as-prepared gas sensor based on MoS 2 /SnS 2 nanocomposites exhibits reliable long-term stability with the maximum response value drift of less than 3% at room temperature. Moreover, the MoS 2 /SnS 2 sensor also possesses desirable gas sensing properties upon NO 2 at room temperature, such as high sensitivity, rapid response/recovery speed (28 s/3 s, 5 × 10 −6 NO 2 ), satisfactory selectivity, favorable repeatability and reversibility. The improved gas sensing properties of MoS 2 /SnS 2 nanocomposites can be attributed to the unique electronic properties of MoS 2 nanosheets with the fewer layers structure and the competitive adsorption effect of SnS 2 nanoparticles. This work elucidates that SnS 2 nanoparticles serving as an effective antioxidative decoration can promote the stability of MoS 2 nanosheets, providing a promising approach to achieve high-stability NO 2 gas sensors at room temperature.