Enhanced NO2-sensing performances of CeO2 nanoparticles on MoS2 at room temperature

The composites of CeO2 nanoparticles and MoS2 nanosheets are prepared by hydrothermal method. It is found that the CeO2/MoS2 composites exhibit the better NO2-sensing response at room temperature (RT), with the sensitivity towards 5 ppm NO2 higher than that of pure MoS2 by 69.1%, and 85% of the resistance can be returned within 900 s. The sensor also possesses the characteristics of a fast response, a reliable long-term stability and an excellent selectivity. Based on the first-principle calculations, the adsorption energy of CeO2/MoS2 composites to NO2 is much higher than that of MoS2, enhancing the adsorption ability of NO2. Moreover, the CeO2/MoS2 composites could suppress the aggregation of nanosheets and nanoparticles, and thus provide plenty of active sites for adsorption of NO2 molecules. As a result, the room-temperature NO2-sensing response is enhanced substantially.

Automated summary

CeO2/MoS2 composites show a superior NO2-sensing response at room temperature, with high sensitivity, fast response, and excellent selectivity.