Organic-functionalized Graphene Oxide for Room Temperature Chemoresistive Gas Sensing

In the wide palette of chemoresistive sensing materials, hybrid nanocomposites have quickly gained a prominent position. So far, the research focused on graphene and graphene-based materials has led to an extensive assortment of highly performing devices, including functionalized graphene oxide (FGO) and its reduced counterpart (rFGO). FGO was proposed for lithium batteries production and other several applications. Since GO and rGO also exhibited very high signal stability, we extended the investigation on their chemoresistive properties. Cyclic ethers functionalization has been explored to optimize the gas sensing properties of this novel class of materials, i.e., cations and polar molecules affinity. Thick-films were deposited onto alumina substrates by drop-casting, the electrical characterization performed revealed significant sensitivity to hydroxyl group at room temperature with fast and reversible response, which notably increased the sensing performances with respect to GO. Such encouraging results have led to the study of different types of polyethers or synthesis parameters, such as ether: graphene and GO reduction rates. Nevertheless, the possibility of metal doping, due to the high stability of metal-cyclic ethers complex, opens up the way to a new class of compounds for gas sensing, owing to the modularity of the employed molecules.