Stretchable sensor shows sensitivity to nitrogen dioxide

The sensor, which has been developed by a team from Penn State University, Northeastern University and five universities in China, is said to combine a newly developed laser-induced graphene foam material with a unique form of molybdenum disulphide and reduced-graphene oxide nanocomposites.

One-step-laser process used to develop highly-sensitive NO2 sensor

According to Penn State, the researchers were interested in seeing how different morphologies of the gas-sensitive nanocomposites affect the sensitivity of the material to detecting nitrogen dioxide molecules at very low concentration. To change the morphology, they packed a container with very finely ground salt crystals.

When the researchers added molybdenum disulphide and reduced graphene oxide precursors to the canister, the nanocomposites formed structures in the small spaces between the salt crystals. They tried this with a variety of different salt sizes and tested the sensitivity on conventional interdigitated electrodes, as well as the newly developed laser-induced graphene platform. When the salt was removed by dissolving in water, the researchers determined that the smallest salt crystals enabled the most sensitive sensor.