In the experiments, we used the gas-phase derivatisation technique (Basiuk et al. 2002), employing the custom-made Pyrex glassware described in detail in the previous chapter of this volume (Fig. 19.1). The sample (fullerene film on a silicon substrate) was placed into the reactor 11. Then a few milligrams of 1,8-diaminooctane were added directly to the reactor bottom, avoiding direct contact with the sample. After pumping the reactor out to ca. 1 Torr at room temperature, its valve 2 was closed, and the bottom was heated at about 150°C for 3 h. During this procedure, 1,8-diaminooctane evaporated and reacted with C6o. The diamine excess condensed a few centimeters above the heating mantle. The high derivatisation temperature not only facilitates the reaction, but also helps to minimise the amount of diamine physically adsorbed on the sample. After finishing the treatment, the reactor valve 2 was open again for ca. 1 h to pump out unreacted diamine. Then the heating mantle was removed, the reactor cooled and disconnected from the manifold. Before unloading the derivatised sample, the upper reactor part with the excess diamine condensed was wiped with cotton wool wet with ethanol. Along with the chemical modification of C60 films, we have similarly performed the reaction of pristine fullerene powder with 1,8-diaminooctane, as a control experiment. It was essentially melting together the two reagents.
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