The electrostatic attraction and coordination interaction between
porphyrin-based supramolecules and silver nanoparticles
may cause the formation of larger aggregates. Typical TEM photographs
of AgNp in the situation after coated with C60-1 and C70-1
suparamolecular systems are shown in Figs. 8a and b, respectively.
Fig. 8a recognizes the formation of low contrast fibrous structure in
presence of C60. However, presence of C70 changes the morphology
in the fibrous structure, and now fibrils show more dense and
strong contrast compared to what we observe in case of C60-1-
AgNp nanocomposite. The novel C70-induced morphological
change is due to a strong C70-1 interaction originated from skillfully
programmed p–p interaction which is not so pronounced in
case of C60-1 system.