Synthesis and characterizations of exohedral functionalized graphene oxide with iron nanoparticles for humidity detection

This paper reports the characterizations and humidity sensing properties of Fe–GO. Thin films of GO and Fe–GO have been made by using the spin coating technique with 1500 rpm. After fabrication of thin film, variations in capacitance of the film with relative humidity (%RH) have been recorded. The thin film has been characterized by various techniques and a unique flower-like structure was found after the functionalization of GO with iron. The XRD analysis confirmed that the GO consists of a minimum of five layers of the graphene. BET surface analysis reveals that the synthesized Fe–GO is the mesoporous material partaking the surface area 45.23 m2/g together with a mean pore diameter of 32 nm. The sensitivity of the Fe–GO based sensor found as 14.12 pF/%RH for higher humidity (70–95%RH) region along with average sensitivity, response and recovery time as 5.18 pF/%RH, 31 s and 11 s respectively at room temperature.