Flexible gas sensor based on MoSe2-Mo2C heterostructure for hydrogen sulfide detection at room temperature

摘要

This study focuses on the development of MoSe2-Mo2C based low cost and flexible gas sensor for the hydrogen sulfide detection at room temperature. A novel material with Mo2C nanoparticles modified MoSe2 (MoSe2/Mo2C) was synthesized by hydrothermal method then calcinated at 780°C. The sensing film was produced by drop casting the dispersed material on top of screen-printed carbon electrodes on a flexible polyethylene terephthalate substrate. These sensors exhibited good mechanical stability and gas-sensing characteristics. It is found that the Mo2C nanoclusters change the surface chemistry of the MoSe2 and enhance its gas sensing properties. Compared to pristine MoSe2 as the sensing material, MoSe2-Mo2C based sensor exhibits a much higher performance, in which the sensitivity has been increased by up to 6 times in the presence of 100 ppb of H2S. The improved sensitivity could be attributed to the increase of adsorption site in the material induced by the incorporation of Mo2C facilitating the charger transfer process. The new sensor possesses good linearity and high sensitivity between 100 ppb and 1 ppm, with good stability and a full recovery at room temperature. This suggests that MoSe2-Mo2C appear as a potential candidate for developing high-performance nanoelectronic devices.