| Tartalmi leírás: |
A new method has been developed to separately study the effects of (i) impurities resulting from the
catalytic chemical vapor deposition synthesis, (ii) the attached functional groups and (iii) the oxidation
debris on the properties of carboxyl-functionalized multiwall carbon nanotubes (CNTs) by incorporating
a Soxhlet-extractor enhanced acetone washing process into the synthesis method. Pd nanoparticles
supported on the carbon nanotubes were investigated in the hydrogenation of cyclohexene to
cyclohexane. Despite the fact that the specific surface area and the Pd dispersion were both low, the Pd/
CNT catalyst with post-synthetic impurities showed 20 times higher catalytic activity compared to
functional group free, acetone-washed samples. Meanwhile oxidation debris originating from the
functionalization was found to affect both the specific surface area and the G/D ratio obtained from
Raman spectra, it had slight effect on the size of the supported Pd nanoparticles or the catalytic activity.
On the other hand, functional groups have a significant effect on the catalytic activity without
influencing the specific surface area, the G/D ratio or the Pd nanoparticle dispersion.
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