Synthesis of Zinc Oxide (ZnO) – Graphene Nanocomposite as CO Gas Sensor Application

In this paper, Carbon Monoxide (CO) gas sensor deposited on the Alumina substrate was fabricated by synthesizing a nanocomposite of Zinc Oxide (ZnO) and Graphene as a sensing layer via the hydrothermal method. ZnO-Gr nanocomposite was varied with ratio of 1:1, 1:3, and 1:5 to obtain the optimum composition in responding to CO gas. The sensing layer was exposed by CO gas to 5 concentration variations at room temperature and 1 concentration at 2 high temperature. Morphological structure of ZnO-Gr was presented through Scanning Electron Microscopy (SEM). It was found that ZnO-Gr nanocomposite with ratio of 1:3 at room temperature generated the highest % response to CO gas sensing. Decreased resistance occurs in step of increasing temperature. The property of semiconductor changes from p to n-type above 100°C temperature to CO gas exposure.