Development of a Fluorinated Graphene-Based Flexible Humidity Sensor

A novel fluorinated graphene-based humidity sensor was successfully developed for humidity monitoring applications. The humidity sensor was fabricated by screen printing silver (Ag) interdigitated electrodes (IDEs) on a flexible polyimide substrate. A fluorinated graphene powder, that was uniformly dispersed in isopropyl alcohol (IPA) using the ultra-sonication process, was drop casted on the IDEs as a humidity sensing layer. The resistive response of the fabricated humidity sensor towards varying relative humidity (RH) levels ranging from 20% RH to 70% RH, in steps of 10% RH, was investigated at a constant temperature of 24 °C. A maximum resistance change of 12.1% was observed when the humidity was changed from 20% RH to 70% RH, with a sensitivity of 0.24 %/%RH.