Flexible graphene-based chemical sensors on paper substrates
Graphene-based, flexible NO2 sensors on paper substrates exhibited an immediate response (32–39%) once exposed to 200 ppm NO2 gas under a strain of 0.5%. Chemical vapor deposition-grown graphene with a supporting poly(methyl methacrylate) layer was transferred onto paper substrates, followed by formation of two electrodes using silver paste. Current–voltage characteristics and dynamic sensing response were obtained under both relaxed and strained conditions. We demonstrate a facile method without complex photo-lithography and high vacuum processes for fabricating graphene-based flexible NO2 sensors on paper substrates with high sensing response.