LC Wireless Passive Humidity Sensor Based On GO-MXENE Composite Material For Human Breathing Monitoring

Humidity monitoring is of great significance to production, quality and resource utilization. Traditional wired humidity sensors are difficult to meet the requirements of the Internet of Things due to their complex wiring, high cost and difficult maintenance. In this study, LC wireless passive technology was applied to the humidity sensor, and a GO-MXENE composite material was used as the humidity-sensitive material to prepare an LC wireless passive humidity sensor for human breath monitoring. The relationship between the resonant frequency of the sensor and humidity was studied, a humidity-resonant frequency coupling model was constructed, and the HFSS simulation software was used to establish a model of the wireless passive humidity sensor with an interdigital structure. The optimal size of the sensor was obtained through optimization. The research shows that when the finger width of the interdigital electrode is 0.3 mm and the finger length is 8 mm, the Q value of the sensor reaches the highest. The test in a constant temperature and humidity chamber shows that under the condition of 30 \u2103, the humidity sensor has a sensitivity of 0.131 MHz\/%RH in the low humidity range of 10%RH - 60%RH, and a sensitivity of 0.367 MHz\/%RH in the high humidity range of 60%RH - 90%RH. The change in resonant frequency can reach 18 MHz, the response time is 7.2 s, and the recovery time is 11.4 s. Moreover, after multiple repeated experiments, it is proved that the sensor has good repeatability and stability.