Design and understanding of SnO2 architecture decorated by MoS2 quantum dots for enhancing triethylamine sensing☆

The size effect through quantum dots is an effective method to improve the performance of gas sensors. This paper reports the design of a triethylamine sensor based on a SnO2-MoS2 heterojunction structure. The porous SnO2 was synthesized using a polystyrene microsphere template and then loaded with MoS2 quantum dots (MoS2 QDs) by the impregnation method. The gas-sensitizing properties of the prepared sensors were systematically investigated. Compared with the single SnO(2 )and MoS2 gas sensing materials, the SnO2-MoS2 sensor showed higher selectivity to triethylamine at the optimal operating temperature of 160 degrees C, and the response performance was improved by 192 %. The results show that the SnO2-MoS2 heterojunction improves the sensing performance due to its unique pore structure, oxygen vacancies and n-n heterojunction. In addition, the energy band structure and triethylamine sensing mechanism of SnO2-MoS2 heterojunctions were analyzed by density functional theory. This work provides significant value for the study of gas-sensitive properties and triethylamine sensors of SnO2 -MoS2 QDs composites.