Plasmonic Au Nanoparticles Sensitized MoS2 for Bifunctional NO2 and Light Sensing

The possibility to synergise two-dimensional (2D) materials with 0D nanoparticles has sparked a surge in high performance futuristic electronic devices. Here, we decorated plasmonic Au nanoparticles on surface of chemical vapor deposition (CVD) grown 2D MoS2 nanosheet and demonstrated bifunctional sensing behaviour within a single device. The plasmonic Au nanoparticles functionalized MoS2 device showed about similar to 5 times higher sensitivity to NO2 than that of pristine MoS2 at room temperature. The enhanced gas sensing performance was attributed to a combination of Schottky barriers modulation at Au/MoS2 nanointerfaces and catalytic effects upon exposing the gas analyte. In addition, the device also exhibited enhanced photoresponse with a high photo-responsivity of similar to 17.6 A/W and a moderate detectivity of similar to 6.6 x 10(11) Jones due to enhanced local plasmonic effects. Finally, photons and gas molecules are detected in sequence, which proved that only a single Au-MoS2 device exhibited remarkable bifunctional sensing characteristics. Such excellent bifunctional sensing ability of a single AuMoS2 device paves the way to integrate the 2D material with plasmonic nanostructures for developing an advanced multifunctional sensor.

Automated summary

Researchers decorated plasmonic Au nanoparticles on the surface of chemically vapor deposition (CVD) grown 2D MoS2 nanosheets, demonstrating bifunctional sensing behavior within a single device with higher gas sensitivity and enhanced photoresponse.