VOC Gas Sensors Fabricated with Graphene Oxide Composites for Food Safety and Quality
In this study, an array of sensors is investigated by employing graphene oxide and nanostructured metal oxide based on SnO2. Their composite films on a series of electrodes are prepared to create a high density of sensing array in a small size chip. A composition gradient sensing layers can produce unique gas response patterns. Figure 1 shows surface morphology of compositionally gradient tin oxides (1:6 ratio of GO to SnO2) and structure property confirmed by XRD result. The results on the growth of nanostructured films using solution process and vacuum process are presented. Figure 2 also shows sensing properties of the composites to formaldehyde gas at room temperature. The combinatorial structure enhances the sensing properties of devices in terms of sensitivity, selectivity and response rate. Additionally, such a sensor can meet the proposed idea, in-situ detection, and also the requirements for low-cost and high-volume production as well as high gas analytical performance.
This research was partially supported by a grant from a Strategic Research Project (2013-0132) funded by the Korea Institute of Construction Technology, and Auburn University IGP.
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