SnO2-based chemiresistive gas sensors can effectively detect combustible, explosive and toxic gases, and have been widely used in safety monitoring and process control in residential buildings, in various industrial settings and in mines. However, sensitivity and selectivity are still needed to be further improved for most current SnO2-based gas sensors. In addition, their high power consumption due to their high working temperature (200-400°C) limits their further development. Graphene, due to its unique characteristics (such as excellent electrical conductivity, large surface-area-to-volume ratio, and high chemical stability) has been foreseen as one of the most promising gas-sensing materials. However, alone, graphene exhibits minimal selectivity. This project aims to synergistically leverage the advantages of graphene and SnO2 to reduce or eliminate the disadvantages of either material by forming graphene/SnO2 composites. Additionally, a hard template method based on polystyrene sphere monolayer colloidal crystals (PSMCC) is adopted to fabricate porous thin films. By determining their specific contents, we aim to achieve highly sensitive and selective humidity detection at room temperature.
Project ended 08/01/2022