CVD-Grown MoS2-Monolayer-Based Ultrasensitive Human Breath Sensor: Experimental and Theoretical Study

This letter demonstrates the fabrication of the MoS
₂
monolayer based breath sensor and the detailed theoretical analysis of the transduction mechanism using first-principal calculations. The theoretical analysis reveals that the water molecules tend to get preferentially and strongly adsorbed on the sulfur vacancy sites on monolayer MoS
₂
. After adsorption, the water donates electrons to the host lattices, leading to an increase in electronic conductivity and subsequent drain current as observed experimentally. The sensor displayed response to varied breath frequencies, thereby having potential applications in breath pattern analysis for disease detection.