Functionalization of carbon nanohorns and their catalysis applications

Abstract

Carbon nanohorns (CNHs) synthesized by gas-injected arc-in-water method were functionalized in this study. Metal (Ni, Cu, Fe, Pd, and Pt) and their alloy (NiCu, NiFe, NiPd, and NiPt) hybridized with CNHs were successfully produced. In addition, thermal and acid treatment was applied on the hybridized materials. Effect of metal loading and functionalizing conditions on characteristics of CNHs and functionalized CNHs was examined based on transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), N2 sorption, Raman spectroscopy, Fourier transform infrared (FT-IR) spectrometer, temperature programmed desorption of ammonia (NH3-TPD) analysis. The functionalized CNHs were applied as a catalyst in 3 difference reactions, namely dehydration of xylose to furfural, esterification of levulinic acid to ethyl levulinate, and transfer hydrogenation of methyl levulinate to ?-valerolactone. Performance and stability of the catalyst was investigated. Moreover, role of the catalyst in each reaction were also discussed.