Closed network growth of fullerenes

Abstract

Tremendous advances in nanoscience have been made since the discovery of the fullerenes; however, the formation of these carbon-caged nanomaterials still remains a mystery. Here we reveal that fullerenes self-assemble through a closed network growth mechanism by incorporation of atomic carbon and C 2 . The growth processes have been elucidated through experiments that probe direct growth of fullerenes upon exposure to carbon vapour, analysed by state-of-the-art Fourier transform ion cyclotron resonance mass spectrometry. our results shed new light on the fundamental processes that govern self-assembly of carbon networks, and the processes that we reveal in this study of fullerene growth are likely be involved in the formation of other carbon nanostructures from carbon vapour, such as nanotubes and graphene. Further, the results should be of importance for illuminating astrophysical processes near carbon stars or supernovae that result in C 60 formation throughout the universe.

Ions colliding with clusters of fullerenes—Decay pathways and covalent bond formations

“…Our observation of a C + 61 peak is thus consistent with the ideas of efficient single C-inclusion in the C 60 cage structure as presented in Ref. 3. However, C 61 ions were not observed directly in that experiment.…”

“…4 In the same experiment, the measured high formation rate of C 70 was rationalized as sequential absorptions of C-atoms and small carbon molecules in outer undamaged C 60 molecules, 4 similar to what was proposed in Ref. 3. Recently, we reported on covalent bond formation reactions induced in interactions between somewhat smaller clusters of C 60 and keV He 2 + ions.…”

“…We believe that this is caused by fragmentation of one or several C 60 molecules in the cluster and absorption of C atoms from such fragmentation processes by intact C 60 molecules during cluster fragmentation. In a recent study, 3 the mass spectra following laser ablation of a fullerene-graphite mixture showed clear evidence of molecular growth processes in which fullerenes larger than C 60 and with even numbers of carbon atoms were produced. As we will demonstrate below, a C + 62 peak will also appear on the side of C + 61 when we increase the cluster sizes.…”

“…However, C 61 ions were not observed directly in that experiment. 3 The narrow components of the peaks in the upper right panel of Fig. 1 are due to clusters of C 60 molecules which have been singly ionized in collisions with Ar 2 + and which remain intact during extraction and acceleration in the timeof-flight spectrometer (cf.…”

Diffuse interstellar bands in fullerene planetary nebulae: the fullerenes – diffuse interstellar bands connection

“…At present, the HAC's photochemical processing is the most likely C 60 formation route in the complex circumstellar envelopes of PNe (García-Hernández et al 2012a;Bernard-Salas et al 2012;Micelotta et al 2012). Larger fullerenes may grow from pre-existing C 60 molecules (Dunk et al 2012) that may be supplied by the photochemical processing of HAC dust, opening the possibility of forming other fullerene-based molecules such as buckyonions and fullerene adducts. Indeed, fullerenes and PAHs may be mixed in the circumstellar envelopes of fullerene PNe (e.g., M 1-20) and fullerene/PAH adducts may form via Dies-Alder cycloaddition reactions (García-Hernández et al 2013).…”