Abstract
Graphene field-effect transistors (GFETs) are a promising candidate for sensing applications because of their high charge carrier mobility, high flexibility, biocompatibility and the ideal coupling between graphene charge carriers and surface potential. Coating graphene with sensing membrane fabricated high-k materials that can be used to pH sensing in aqueous solutions. This work presents the development of an analytical model for GFET-based pH sensor. This model can help in the investigation of the sensitivity mechanism related to the ambipolar characteristic of the GFET and theory of site binding and a Gouy–Chapman–Stern model. Finally, simulation results are compared with those extracted from experimental measurements and a good agreement is observed which validates the proposed analytical model.