Abstract: Control and monitoring of volatile organic compounds (VOC) have gained increasing concern in recent years, which greatly promoted the development of chemical sensors. Recognition and quantification of VOC using non-selective chemical sensor requires a combination of sensors followed by pattern recognition methods. Based on this concept, this paper deals with the discrimination of gas from the responses of several quartz crystal microbalance (QCM)-based sensors coated from different organosilicon monomers. The sensitivity of the elaborated QCM-based sensors was evaluated by monitoring the frequency shifts (?f) of the quartz exposed to different concentrations of ethanol, benzene and chloroform. Structural and morphological analyses of the sensitive coating have been carried out by Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM), respectively. For all types of analyte, ?f were found to be linearly correlated with the concentration of VOC vapor. It was shown that it is possible to tune the chemical affinity of the sensor by changing the monomer types. An array of organosilicon layers, with each film having different sensing characteristic, provided good vapor discrimination and quantification when exposed to a series of organic vapors. The principal component analysis (PCA) and the neural network (NNs) pattern recognition analysis were used for the discrimination of gas species and concentrations. Good separation among gases has been obtained using the PCA and NNs. It is concluded that with an appropriate choice of coatings coupled with an adequate pattern recognition method, the whole sensor may have much better selectivity than do its individual adsorbing sites.
N° Revue: Sensor Letters - Pagination: 259-266 - Date: 2015
URL: http://www.ingentaconnect.com/content/asp/senlet/2015/00000013/00000003/art00012?crawler=true
Mots cles: ORGANOSILICON FILM; PATTERN RECOGNITION ANALYSIS; PLASMA; QCM MULTI SENSORS; VOC
co_auteurs: Lezzar, Omar. C.; Bellel, A.; Boutamine, M.; Sahli, S.; Segui, Y.; Raynaud, P