Self‐Powered Graphene Oxide Humidity Sensor Based on Potentiometric Humidity Transduction Mechanism

Abstract Non‐contact humidity sensors have been widely explored as human–computer interaction for the internet of things and artificial intelligence. However, except for the existing sensing mechanisms, such as resistive, capacitive, and functional groups gradient based device, little attention has been paid to exploiting new sensing mechanisms with novel properties which can meet the requirements of miniaturization and integration. Here, a self‐powered potentiometric humidity‐transduction mechanism, which modulates the measured potential difference between two electrodes by humidity stimulation on the graphene oxide (GO) solid electrolyte, is reported. On the strength of this mechanism, a highly adjustable potentiometric humidity sensor with sandwich structure of reduced graphene oxide/GO/foamed metal (nickel, zinc, iron and copper), exhibiting good scalability and cost‐efficiency, enabling fast response/recovery (0.8 s/2.4 s), ultra‐high response (0.77 V) and excellent stability (over 1500 cycles) is developed. Unlike traditional sensing mechanisms, the manipulation mechanism raised here shows self‐powered ability with no need for an additional power unit and has ultra‐low power consumption. These results provide a new scheme for the research and development of self‐powered humidity sensors, and these sensors show superior performance in non‐contact sensing applications.