High-Performance Atomically-Thin Room-Temperature NO Sensor.

The development of room-temperature sensing devices for detecting small concentrations of molecular species is imperative for a wide range of low-power sensor applications. We demonstrate a room-temperature, highly sensitive, selective, stable, and reversible chemical sensor based on a monolayer of the transition-metal dichalcogenide ReNbS. The sensing device exhibits a thickness-dependent carrier type, and upon exposure to NO molecules, its electrical resistance considerably increases or decreases depending on the layer number. The sensor is selective to NO with only minimal response to other gases such as NH, CHO, and CO. 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. We present a theoretical analysis of the sensing platform and identify the atomically sensitive transduction mechanism.