Supramolecular fabrication of polyelectrolyte-modified reduced graphene oxide for NO2 sensing applications

This paper reports the supramolecular fabrication of polyelectrolyte-modified reduced graphene oxide (rGO) nanocomposites and their applications towards NO2 gas sensors. To prepare the composite materials for sensing applications, rGO was used as a template which was readily prepared through the reduction of hydrazine hydrate. By using a facile and effective supramolecular assembly (SA) method, two nanocomposites, i.e. poly(allylamine hydrochloride)–rGO (PAH–rGO) and polystyrenesulfonate-rGO (PSS–rGO) were prepared and efficiently used as effective materials to fabricate highly sensitive and stable NO2 gas sensors. The prepared nanocomposites were examined using several techniques which confirmed the successful formation of PAH–rGO and PSS–rGO nanocomposites. By detailed sensing experiments, it was found that both PSS–rGO and PAH–rGO nanocomposites exhibited strong gas sensing response, good stability and favorable reversibility for the detection of NO2 gas. Finally, NO2 gas sensing mechanisms, based on the utilization of specific nanocomposites, were also discussed and presented in this paper.