Fabrication of MoS2-Fe3O4 heterostructure as an ultrafast and high-sensitivity NO2 gas sensor at room temperature

In this study, a novel MoS2-Fe3O4 heterostructure was fabricated for efficient detection of NO2 gas. The structural and morphological properties of MoS2-Fe3O4 composites were investigated by relevant characterization methods. The NO2 sensing performance of the sensor based on MoS2-Fe3O4 was tested. The result demonstrated that the MoS2-Fe3O4 sensor showed excellent performance with a high response of 25 and a fast response time of 6 s as exposed to 5 ppm NO2 at room temperature. In addition, this sensor also exhibited high sensitivity, satisfactory selectivity, excellent moisture resistance, favorable reproducibility and long-term stability. The enhanced gas sensing performance can be attributed to the synergetic effect of the abundant oxygen vacancy and p-n heterojunction.