Highly Sensitive and Fast-Response Humidity Sensor Based On Saw Resonator and MoS2 for Human Activity Detection

In this paper, a humidity sensor based on surface acoustic wave (SAW) resonator and Molybdenum disulfide (MoS
₂
) is proposed for high performance. A graphene oxide (GO) film is firstly coated on the resonator as isolated layer, then a MoS
₂
film was coated as sensing layer. The proposed humidity sensor has advantages of high sensitivity (12.41 kHz/%RH), low hysteresis (4.32%), high stability (variation≈1%), fast response (0.4 s) and recovery (0.8 s) time. Based on this high-performance sensor, we demonstrate applications of human breath monitoring and noncontact detection of finger motion.