PEDOT:PSS-Based Disposable Humidity Sensor for Skin Moisture Monitoring

Abstract

This paper presents a flexible and disposable humidity sensor based on Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). The sensing layer is developed by drop casting PEDOT:PSS on screen printed graphene-carbon (G-C) ink based interdigitated electrodes (IDEs) on paper substrate. The humidity sensing properties are investigated in a wide humidity range (25%RH - 90%RH) at room temperature (RT; 27 °C ± 2 °C). The sensor exhibits substantial % response (118.5% at 90%RH) in the considered range with response/recovery time as 70/30 seconds (sec). The applicability of the sensor has been demonstrated for skin moisture/humidity monitoring under normal and moist conditions. A read-out circuit is designed for demonstrating the real-time monitoring of skin moisture level. The obtained results indicate the suitability of the developed sensor for skin moisture monitoring, environmental humidity monitoring, and non-contact switching is areas such as healthcare and agriculture.