Graphene–Fe3O4/PIL–PEDOT for the design of sensitive and stable quantum chemo-resistive VOC sensors

Quantum chemo-resistive vapour sensors have been synthesised from the assembly of magnetic nanoparticles-decorated reduced graphene oxide (Fe3O4–RGO) with poly(3,4-ethylene dioxythiophene) (PEDOT) and poly(ionic liquid) (PIL). This new hybrid sensing material demonstrated enhanced sensitivity, selectivity, signal-to-noise ratio and reduced response time compared to its elementary constituents (also sensitive), which suggests that a positive synergy of properties has been reached through the structuring of the conducting architecture by spray layer-by-layer. The Fe3O4-RGO/PIL–PEDOT sensor exhibited stable and reproducible signals at room temperature for both polar (ethanol, methanol, acetone, water) and non-polar (chloroform, styrene, dichlorobenzene, toluene) volatile organic compounds (VOC), considered as food degradation biomarkers. Since sensor’s responses are still well defined at the ppm level (and may be even at the subppm level) as attested by a SNR around 10, an application such smart packaging could be envisaged.