소수성 기능화를 통한 내습성 환원 그래핀옥사이드 기반 가스센서 개발

Abstract

This paper presents the synthesis and fabrication of lanthanum oxide functionalized reduced graphene oxide gas sensors to reduce the humidity effect. Reduced graphene oxide (rGO) have been widely studied in gas sensing application owing to large surface area, and room temperature operation. Additionally, oxygen functional contents on rGO surface play an important role in gas detection as they are active sites for the gas adsorption. However, such groups cannot differentiate between target gas and water molecules. To reduce the humidity effect of gas sensors, lanthanum oxide (La2O3), being one of rare-earth oxide ceramics, have been employed owning to its intrinsically hydrophobic property. rGO have been obtained through n-Hexanol reduction process, and hydrothermal synthesis makes La2O3 functionalized rGO powders. We have characterized the powders using FT-IR, XPS, and Raman spectra to check functional groups on rGO surface. In gas sensing chamber, the relative humidity is controlled ranging from 10 to 70%. We believe that hydrophobic properties of La2O3 could reduce the humidity effect of gas sensors regarding measurement sensitivities.