A QCM Humidity Sensor Based on MoS₂ Nanoflower-Modified Chitosan Composite With High Quality Factor

This article presented a quartz crystal microbalance (QCM) humidity sensor covered with chitosan/molybdenum disulfide (CS/MoS2) composite film. The prepared sensor possesses promising humidity sensing performance with high sensitivity [46.06 Hz/% relative humidity (RH)], short response/recovery time (15/3 s), and small humidity hysteresis (2.5% RH). Most notably, the MoS2 nanoflowers that play a supporting role in the CS/MoS2 composite significantly reduce the swelling effect of CS in humid environments, enabling the CS/MoS2-based QCM humidity sensor to maintain a high ${Q}$ -factor even under high humidity conditions, thereby considerably improving the stability of the sensor.