CO2 Gas Sensors Based on Hydrophilic Vanadium Oxide Thin Film Coated QCM

Air pollution, which continues to increase, gives rise to considerable concern. It is generated by energy production, industrial activities, agriculture and transport. The main gases responsible for this pollution are sulfur dioxide (SO2), nitrogen oxides (NOx) and carbon dioxide (CO2). Nowadays, carbon dioxide is one of the main gases to detect. In the present work, vanadium oxide thin film has been deposited on quartz crystal microbalance (QCM) using vacuum thermal evaporating method followed by thermal treatment, for CO2 gas sensor. The QCM covered with vanadium oxide film was heated at 200 °C for different times. The annealing time effect on the morphology and surface wettability of these structures has been investigated by using atomic force microscopy (AFM) and contact angle measurements (CA). The results show that elaborated surface exhibited roughness surface and Hydrophilic character. In addition, the exposing of this structure to CO2 gas shows that the fabricated structure can be used as a CO2 sensor at room temperature.