Title: | Chemical VOC sensing mechanism of sol-gel ZnO pellets and linear discriminant analysis for instantaneous selectivity |
Author(s): | Souissi R; Bouricha B; Bouguila N; El Mir L; Labidi A; Abderrabba M; |
Address: | "Universite de Carthage, Laboratoire des Materiaux, Molecules et Applications IPEST BP 51 La Marsa 2070 Tunisia riadhsouissi1@gmail.com +21628419444. Laboratoire de Physique des Materiaux et des Nanomateriaux applique a l'environnement, Faculte des Sciences de Gabes, Universite de Gabes Cite Erriadh, Zrig 6072 Gabes Tunisia. Department of Physics, College of Science and Art at Ar-Rass, Qassim University Buraydah 51921 Saudi Arabia" |
ISSN/ISBN: | 2046-2069 (Electronic) 2046-2069 (Linking) |
Abstract: | "This work reports on the integration of ZnO pellets for use as a virtual sensor array (VSA) of volatile organic compounds (VOCs). ZnO pellets consist of nano-powder prepared using a sol-gel technique. The microstructure of the obtained samples was characterized by XRD and TEM methods. The response to VOCs at different concentrations was measured over a range of operating temperatures (250-450 degrees C) using DC electrical characterization. The ZnO based sensor showed a good response towards ethanol, methanol, isopropanol, acetone and toluene vapors. We note that the highest sensitivity (0.26 ppm(-1)) is obtained with ethanol while the lowest one (0.041 ppm(-1)) corresponds to methanol. Consequently, the limit of detection (LOD) estimated analytically reached 0.3 ppm for ethanol and 2.0 ppm for methanol at an operating temperature of 450 degrees C. The sensing mechanism of the ZnO semiconductor was developed on the basis of the reaction between the reducing VOCs with the chemisorbed oxygen. We verify through the Barsan model that mainly O(-) ions in the layer react with VOC vapor. Furthermore, dynamic response was investigated to construct mathematical features with distinctly different values for each vapor. Basic linear discrimination analysis (LDA) shows a good job of separating two groups by combining features. In the same way we have shown an original reason embodying the distinction between more than two volatile compounds. With relevant features and VSA formalism, the sensor is clearly selective towards individual VOCs" |
Notes: | "PubMed-not-MEDLINESouissi, R Bouricha, B Bouguila, N El Mir, L Labidi, A Abderrabba, M eng England 2023/07/12 RSC Adv. 2023 Jul 10; 13(30):20651-20662. doi: 10.1039/d3ra03042c. eCollection 2023 Jul 7" |