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تسجيل مستخدم جديدInvestigation of the Thermal Stability of the Carbon Framework of Graphene Oxide
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In this study, we use our recently prepared graphene oxide (GO) with an almost intact {sigma}-framework of C-atoms (ai-GO) to probe the thermal stability of the carbon framework for the first time. Ai-GO exhibits few defects only by preventing CO2 formation during synthesis. Ai-GO was thermally treated before chemical reduction and subsequently the resulting defect density in graphene was determined by statistical Raman microscopy. Surprisingly, the carbon framework of ai-GO is stable in thin films up to 100 {deg}C. Furthermore, we find evidence for an increasing quality of ai-GO upon annealing at 50 {deg}C before reduction. The carbon framework of GO prepared according to the popular Hummers method (GO-c)appears to be less stable and decomposition starts at 50 {deg}C what is qualitatively indicated by CO2-trapping experiments in {mu}m-thin films. Information about the stability of GO is important for storing, processing and applying GO in applications.
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