Good triethylamine sensing properties of Au@MoS2 nanostructures directly grown on ceramic tubes

Abstract

Due to the extensive threat from TEA, the need for a simple and effective gas sensor for TEA detection is highly desired. Here, the design of the Au nanoparticles was deposited on the surface of the three-dimensional (3D) MoS2 nanostructures, and an excellent TEA gas sensor was successfully fabricated. The 3D MoS2 nanostructures are grown directly on the Al2O3 tubes with a simple and inexpensive hydrothermal process. Au nanoparticles are loaded on MoS2 nanostructures via DC-sputtering in a highly controllable and reproducible manner. Compared to the original MoS2 sensor, Au@MoS2 exhibits a remarkably higher response and faster recovery speed to TEA gas at 280 °C. The influence of the amount of Au on the device performance is also studied, which is controlled by changing the Au sputtering time (0, 30, 50, and 70 s). It is noteworthy that the Au@MoS2 sensor with a medium content (50 s) exhibits the highest response, which is about 4 times higher than that of original MoS2. The enhanced sensing property of the Au@MoS2 sensors is discussed with the semiconductor electron depletion layer model introduced by Au–MoS2 Schottky contact.