Characterization of oxidized SWCNTs by XPS

The chemistry of single walled carbon nanotubes is well developed since Haddon et al described the amidation of the carboxylic acid groups of oxidized SWCNTs. A large number of different reactions have previously been investigated. Covalent modifications of the sidewall with nitrenes, carbenes and radicals are also still possible. However, the characterization of functionalized nanotubes is still non‐trivial. H‐atoms of the addends can be investigated with proton NMR spectroscopy. The disadvantage of this method is that one can see the interaction between the addend and the tubes but not the tube itself. Using Raman‐ and NIR‐spectroscopy only the behavior of the nanotubes can be observed. For microscopic methods, one needs a significant large addend or atomic resolution. In addition to this we present a detailed description of the modified nanotubes with XPS spectroscopy. Here, we can describe the electronic structure and environment of the elements in the sample.