Figure 6. Ability of bio-inspired fabricated nanostructures, natural Morpho scales and QCM and MOX sensor arrays to quantify individual model vapours and their mixtures in the presence of water vapour background.

(a) Designed map of concentrations of two individual model vapours and their binary mixtures mixed with water vapour for studies of responses of sensors, (b–g) PCA scores plots of responses of tested sensor systems to vapours and their mixtures. Sensors: (b) FS-functionalized natural Morpho scales and (c) FS-functionalized fabricated nanostructure—response to methanol and propanol in the presence of water. (d) bare and (e) FS-functionalized fabricated nanostructures—response to methanol and ethanol in the presence of water. (f) QCM and (g) MOX sensor arrays—response to methanol and ethanol in the presence of water. Concentrations of methanol, ethanol and propanol, 0.05, 0.07, 0.09 and 0.11 P/P₀. Concentration of water vapour, 0.4 P/P₀. Vapour labels: methanol (CH₃OH), ethanol (CH₃CH₂OH), propanol (CH₃CH₂CH₂OH) and water (H₂O). Contributions of PCs of different sensors are summarized in Supplementary Table 2 and Supplementary Note 4.