Chemically modified graphene/PEDOT:PSS nanocomposite films for hydrogen gas sensing

In this study, we report the preparation of chemically modified graphene/(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) nanocomposites and their application in hydrogen (H2) gas sensing materials. The aqueous dispersions of graphene oxide (GO) and reduced graphene oxide (rGO) nanosheets were synthesized and further doped into the solution of PEDOT:PSS in dimethylsulfoxide (DMSO). Both the GO/PEDOT:PSS and rGO/PEDOT:PSS composite devices showed a decrease in the resistance upon hydrogen exposure at room temperature. The GO/PEDOT:PSS, a strong p-type material, formed by rectifying contact with tungsten was evaluated for the H2 gas sensing and identified as a contact-controlled type. The rGO/PEDOT:PSS, a weak n-type material, forming an ohmic contact with tungsten was investigated for its H2 gas sensing and identified as a body-controlled type.