Facile fabrication of graphene oxide/Nafion/indium oxide for humidity sensing with highly sensitive capacitance response

A high-performance graphene oxide/Nafion/indium oxide (GO/Nafion/In2O3) humidity sensor is demonstrated in this paper. The morphology and nanostructure of nanocomposites were characterized by SEM, TEM, XRD, BET and XPS measurements. The humidity measurement platform was established by using saturated salt solutions and the 0-97% RH levels were achieved at 25 degrees C to investigate its humidity-capacitance performance. The GO/Nafion/In2O3 film humidity sensor exhibited ultrahigh sensitivity, low hysteresis, good stability and outstanding repeatability. Furthermore, the possible humidity sensing mechanism of the GO/Nafion/In2O3 sensor was discussed by complex impedance spectroscopy and Bode diagrams. The GO/Nafion/In2O3 nanocomposite based capacitance-type humidity sensor is promising in many fields for humidity sensing.