(Invited) Flexible 3-Dimensional Graphene Foam-Based NO 2 Gas Sensors

Abstract

Flexible three-dimensional (3-D) graphene foam-based NO 2 gas sensors on polyethylene terephthalate (PET) substrates were demonstrated. The thickness of graphene layers was analyzed by micro-Raman spectroscopy. Currents of the relaxed and strained (1%) 3-D graphene foam-based NO 2 gas sensors after the repetitive exposure of 200 ppm NO 2 gas for 3 minutes were increased by ~ 0.42 mA and ~ 0.35 mA, respectively. The changes in currents and resistance in different strain conditions were also characterized. The robustness, excellent electrical conductivity and high surface-to-volume ratio of 3-D graphene foam show great potentials for advanced flexible gas sensors.