Characterization of carbon nanofiber composites synthesized by shaping process

Catalytically grown carbon nanofibers (CNFs) are shaped into pellets in desired size and configuration by a conventional molding process so as to extend the potential applications of CNFs in industrial heterogeneous catalysis. After shaping, a novel carbon nanofiber composite with sufficient mechanical strength is produced, in which isolated CNFs are connected by a carbon network formed through polymer binder carbonization. Characterization of the synthesized CNF composite is performed by using HRTEM, XRD, Raman, N₂ physisorption, TPD and TGA. A comparison of the textural and structural properties, as well as the surface chemistry is made amongst the CNFs, the CNF composite, and a commercial coal-based activated carbon, in order to attain a comprehensive understanding of the CNF composite. The results show that the CNF composite preserves the mesoporous texture of the CNFs which will be beneficial to those reactions of mass transfer control. The modification effect of oxidative treatments on physico-chemical properties of the CNF composite is also investigated. More surface oxygen-containing groups are introduced to the composite by treating the material either in boiling HNO₃ solution or in static air at 400 °C.