Fast response humidity sensor based on graphene oxide films supported by TiO2 nanorods

This paper suggests a novel humidity sensor based on graphene oxide sensing film supported by TiO2 nanorods which are grown between Au electrodes via hydrothermal method. The supported structure allows water molecules to pass through TiO2 nanorods and spread to the lower surface of the sensing film, which increases the utilization of the lower surface of graphene oxide (GO) film for humidity detection. Hence, water molecules can diffuse rapidly on both sides of GO film, which will assist in reducing the response time of the sensor. The SEM morphology characterization shows that the supported structure is feasible, and the response curve proves that the response speed of the humidity sensor is improved. The complex impedance spectra (CIS) results are utilized to analyse the response characteristics of the sensor at low humidity level.