The sensor is selective to NO2 with only minimal response to other gases such as NH3, CH2O, and CO2.
The highly sensitive, selective, stable, and reversible chemical sensor is based on a monolayer of the transition-metal dichalcogenide Re0.5Nb0.5S2.
The sensor is able to detect ultralow concentrations of nitrogen dioxide of at least 50 parts per billion, says researcher Amin Azizi.
In the presence of humidity, not only are the sensing properties not deteriorated but also the monolayer sensor shows complete reversibility with fast recovery at room temperature.
When a sensor based on molybdenum disulfide or carbon nanotubes detects nitrogen dioxide, it can take hours to recover to its original state at room temperature. “Our sensor takes just a few minutes,” says Azizi.