Enhanced triethylamine sensing properties by designing Au@SnO2/MoS2 nanostructure directly on alumina tubes

Two dimensional semiconductors are promising gas sensing materials due to their large surface-to-volume ratio. However, some drawbacks just like low response, long recovery time, and insufficient selectivity limits the development of two dimensional semiconductors gas sensors. In order to optimize the gas sensing properties of MoS2 sensors, tri-material compound nanostructure of sensing materials is designed and synthesized by depositing Au and SnO2 nanoparticles on the surface of MoS2 nanoflowers. Comparing with the pristine MoS2 sensor, the Au@SnO2/MoS2 sensor exhibits better sensing properties to triethylamine, such as higher sensitivity and faster response/recovery speed. The enhanced sensing properties of Au@SnO2/MoS2 sensor are discussed from the points of Au@SnO2 Schottky contact and SnO2/MoS2 N-N heterojunction on the basic of depletion layer model. Moreover, MoS2 nanoflowers are directly grew on Al2O3 tubes via a facile and cost-effective hydrothermal method. And the construction of Au nanoparticles decorated SnO2/MoS2 nanoflowers heterostructure were built by employing the pulsed laser deposition and DC-sputtering methods. (C) 2017 Published by Elsevier B.V.