Examination Of Graphene Oxide Or Graphene Nanosheets As Stationary Phase For Capillary Gas Chromatography

Carbon-based nanomaterials have attracted extensive attention these years.Here, we fabricated graphene oxide (GO) nanosheets coated capillary column byone-step fabrication, and graphene (G) coated capillary column statically.Chromatographic performances of two kinds of columns were evaluated.This thesis included three sections:The first section gave brief description about the development of the stationaryphase of gas chromatography. The structures, fabrications, overviews of GO and Gwere also presented. Then the separation performances of GO and G in the field ofanalytical chemistry were introduced, as well as the purpose of this subject and itssignificance.In the second section, two kinds of capillary columns in gas chromatographywere prepared. The GO column, using3-aminopropyldiethoxymethyl silane(3-AMDS) as coupling agent, was fabricated via a new one-step coating approachwhich mixed GO with3-AMDS uniformly. For another, G was dispersed in CH2Cl2and coated on to a capillary column statically.The third section was mainly about evaluation of chromatographic columnperformances. The polarity of stationary phase was characterized by McReynoldsconstants. Separation performances and efficiencies of the capillary columns wereevaluated by separation of different analytes including alkanes, alcohols, esters, aldehydes,ketones, BTEX, halogenated benzenes, PAHs, anilines, the Grob and other mixtures. Thethermodynamics of GO column was also investigated by measure of entropy change andenthalpy change. Additionally, the thermal stability and repeatability of the columns wereevaluated. The results showed that the G column did not show appreciable baseline drift ordecrease in retention time after being conditioned at290℃, which demonstrating the goodthermal stability of the as-prepared column and can be used for practical applications.