Electrical response of GO gas sensors

Abstract

In this paper we report a study of the electrical response to NO2, CO, H2O and H2 of a graphene oxide (GO) based gas sensor. The device has been operated in the temperature range 25– 200◦C at different gases concentrations (1–200 ppm). Micro structural physical features of the GO sensing films were characterized by Raman and X-Ray Photoelectron Spectroscopy, and by Scanning Electron Microscopy. The GO based sensor has shown high sensitivity to NO2 (down to 1 ppm) at 150◦C operating temperature, analogous to a p-type response mechanism of inorganic gas sensors. The NO2 adsorption/desorption has been found to be reversible, but with increasing desorption time when decreasing the operational temperature. Negligible response to CO, H2 and v has been observed. The observed gas sensing performance of the GO based sensor is similar to the best one reported in literature for carbon nanotubes.