Pt-decorated MoS2 rose-like microspheres for highly sensitive NO2 gas detection

In this work, we prepared rose-like MoS2 microspheres by using a simple hydrothermal route. It is found that synthesis temperature is a decisive factor influencing the morphology of MoS2 products. The rose-like MoS2 microspheres were obtained at 210 degrees C. To enhance the gas-sensing properties, noble metal Pt was employed to decorate MoS2 microspheres. Compared to the bare MoS2, the 0.10Pt-MoS2 sensors show higher sensitivity, better repeatability, and more excellent selectivity towards NO2 at the optimal operating temperature of as low as 150 degrees C. The 0.10Pt-MoS2 sensors also exhibit a fast response and recovery time of 21 s/173 s to 32 ppm NO2. The enhanced sensing properties are primarily due to the strong spill-over effect of Pt and modulated Schottky barrier between Pt and MoS2. Our results indicate that the Pt-MoS2 sensors are a promising candidate for detecting toxic and harmful gases in practical use.