Preparation And Catalytic Performance Of Graphene Oxide Based Rare Earth Composite

Natural gas has been extensively investigated as a clean and efficient resource for environmentally producing energy. Whereas, methane is sometimes residual in the exhaust,thus resulting in environmental pollution. Therefore, it is essential to develop efficient catalysts for methane complete oxidation at lower temperature. In this study, a series of graphene oxide based rare earth composite with newly surface texture structure was created,which could facilitate the catalytic combustion of methane. These catalysts were promising catalyst for catalytic methane combustion in various applications to take the place of noble metal catalysts.In this study, La CoO3 was synthesized and then added in graphene oxide/LaCO3OH/Co3O4 composite catalysts(GO/LCH/Cos) preparation using hydrothermal process, with urea and graphene oxide as addictives. The effects of reaction time, reaction temperature, addictive amount on phase composition, microstructure, surface properties and reduction property of catalysts were characterized by XRD, TEM, BET,SEM, H2-TPR and XPS.The activity mechanism of catalysts was also investigated.Results indicated that the reaction time and temperature had great impact on the LaCO3OH/ Co3O4 catalysts, which were prepared with only the urea as addictive. The optimum conditions was hydrothermal treatment at 180℃ for 24 h, and the as-prepared catalyst showed best activity.Results of the amount of urea and graphene oxide on the structure and activity of GO/La CO3OH/Co3O4 catalysts hydrothermal treated at 180℃ for 24 h was also obtained.The results showed that the optimal addictive amount of graphene oxide and urea is 2% and the optimal addictive amount of urea is 5 times to that of LC, and the light-off temperature of the catalyst was 315℃, while the temperature of complete conversion was 420℃. Various characterizations suggested that this obtained catalyst had a unique load-structure and good dispersibility, which facile the exposure of active matter. Morever, the high oxygen vacancy formed and resulted in good catalytic activity at lower temperature.