Fig. 7
Electric methodology for VOC gas detection. a VOC gas detection using acoustic resonators based on the gravimetric mechanism (Lu et al. 2015). i: Schematic of the FBAR sensor array functionalized with four supramolecular monolayers. ii: Schematic of the device section. iii: SEM image of the device. iv: Schematic diagram of VOCs adsorption. v: Real-time responses of the FBAR sensor with exposure to chloroform gas. vi: Adsorption isotherms of chloroform. b VOC gas detection using semiconducting metal oxide (Li et al. 2017). i: A Reaction mechanism of the sensor for HCHO detection. ii: SEM images of as-synthesized SnO2 microspheres. iii: Dynamic response-recovery curve of the SnO2 microspheres gas sensor. c Machine learning-enabled graphene electronic nose for VOC gas detection (Capman et al. 2022). i: Schematic of the ML-enabled sensor system. ii: PCA score plots showing the projection of the measured responses onto principal components 1 and 2. iii: Confusion matrix