Design and fabrication of CNT/graphene-based polymer nanocomposite applications in nanosensors

Development and improvement of nanosensors have been active research areas over the last few decades. Many materials and compounds have been investigated for their sensing properties. This work is concerned with developing a new sensing layer for gas sensors based on chitosan as a polymer enhanced with graphene as a nanofiller. The graphene used for preparing the chitosan solution was at 0.1, 0.5, and 1 wt%. Many characterizations (such as using different pore size, gas permeability, mechanical properties, and electrical resistance) were tested to give full insight into the nanocomposite. Oxygen was utilized as a sample gas for carrying out characterizing tests. The composite was found to demonstrate unique behavior: it was found to have a higher gas concentration gradient with decreasing graphene concentration, and higher electrical conductivity with increasing graphene concentration. These two criteria could be utilized to sense gases in two different ways, both mechanically and electrically. Further investigations were suggested to be carried out in the future to set the conditions (like air pressure, room temperature, ultraviolet light, etc.) for gas sensing. © 2020 Elsevier Inc. All rights reserved.