High-response room-temperature NO₂ gas sensor fabricated with thermally reduced graphene oxide-coated commercial...

Electronic textile-based gas sensors with a high response for NO₂ gas were fabricated using reduced graphene oxide (rGO)-coated commercial cotton fabric (rGOC). Graphene oxide (GO) was coated on cotton fabric by simply dipping the cotton into a GO solution. To investigate the relationship between the degree of reduction and the sensing response, the GO-coated fabrics were thermally reduced at various temperatures (190, 200, 300, and 400 °C). The change in the amount of oxygen functional groups on the rGOCs was observed by x-ray photoelectron spectroscopy, Raman spectroscopy, and x-ray diffraction patterns. The maximum sensing response of 45.90 % at 10 ppm of NO₂ gas at room temperature was exhibited by the rGOC treated at 190 °C, which was the lowest heat-treatment temperature. The high response comes from the greater amount of oxygen functional groups compared to other rGOC samples, and the tubular structure of the cotton.