Capacitive NO Detection Using CVD Graphene-Based Device.

A graphene-based capacitive NO sensing device was developed by utilizing the quantum capacitance effect. We have used a graphene field-effect transistor (G-FET) device whose geometrical capacitance is enhanced by incorporating an aluminum back-gate electrode with a naturally oxidized aluminum surface as an insulating layer. When the graphene, the top-side of the device, is exposed to NO, the quantum capacitance of graphene and, thus, the measured capacitance of the device, changed in accordance with NO concentrations ranging from 1-100 parts per million (ppm).