Room temperature ammonia gas sensor based on Au/graphene nanoribbon

Abstract

Graphene nanoribbon (GNR) is a strip and 1D shape of graphene which can be an appropriate candidate for gas sensing application due to its significant electrical and chemical characteristic. In this study, graphene nanoribbon is employed for the NH3 detection process. The chemical approach is applied for unzipping MWCNTs by using KMnO4, as an oxidative material in graphene oxide nanoribbon synthesis process. The gold comb-like electrodes as a sensor structure is produced by standard deposition and photolithography methods. The quality of the synthesized GNRs is investigated by different analyses such as SEM, XRD, Raman Spectroscopy, and FTIR. In addition to GNR sensor preparation, AuGNR sensor is fabricated by gold sputtering deposition on a GNR sensor surface. The experimental results for sensors indicate that AuGNR and GNR sensors could be the appropriate choices for NH3 detection. The experimental tests for AuGNR and GNR sensors are performed for different NH3 concentration at room temperature which showed 34% and 12.1% response for 25 ppm NH3 respectively. Furthermore, in 25 ppm for the AuGNR sensor, the sensor shows 224 s for response time, and 178 s for recovery time for a graphene-based sensor. All the tests are carried out at room temperature.