Memory effect in the deposition ofC20fullerenes on a diamond surface

Abstract

In this paper, the deposition of C 20 fullerenes on a diamond (001)-(2ϫ1) surface and the fabrication of C 20 thin film at 100 K were investigated by a molecular dynamics ͑MD͒ simulation using the many-body Brenner bond order potential. First, we found that the collision dynamic of a single C 20 fullerene on a diamond surface was strongly dependent on its impact energy. Within the energy range 10-45 eV, the C 20 fullerene chemisorbed on the surface retained its free cage structure. This is consistent with the experimental observation, where it was called the memory effect in ''C 20 -type'' films ͓P. Melion et al., Int. J. Mod. B 9, 339 ͑1995͒; P. Milani et al., Cluster Beam Synthesis of Nanostructured Materials ͑Springer, Berlin, 1999͔͒. Next, more than one hundred C 20 ͑10-25 eV͒ were deposited one after the other onto the surface. The initial growth stage of C 20 thin film was observed to be in the three-dimensional island mode. The randomly deposited C 20 fullerenes stacked on diamond surface and acted as building blocks forming a polymerlike structure. The assembled film was also highly porous due to cluster-cluster interaction. The bond angle distribution and the neighbor-atomnumber distribution of the film presented a well-defined local order, which is of sp 3 hybridization character, the same as that of a free C 20 cage. These simulation results are again in good agreement with the experimental observation. Finally, the deposited C 20 film showed high stability even when the temperature was raised up to 1500 K.

Ab initio insight into the electrolysis of water on basal and edge (fullerene C20) surfaces of 4 Å single-walled carbon nanotubes

“…This highly negative adsorption energy should be attributed to the presence of extremely reactive dangling bonds on the spherical surface of fullerene C 20 . 35 Adsorption of OH/H allows elimination of dangling bonds and thus stabilizes the surface.…”

Structural and electronic properties of zigzag carbon nanotubes filled with small fullerenes

“…In recent years the interest in fullerenes smaller than C 60 has considerably increased after the chemical synthesis of the cage C 20 [16] and studies of the amazing thermodynamical stability of the fullerenes C i (i = 30-82) [17,18]. Using molecular dynamics simulations, Du et al [19] have studied the deposition of C 20 fullerenes on a diamond surface used to produce diamondlike carbon films [20]. Recently, Zhou et al [21] have theoretically investigated threedimensional configurations of encapsulated C 20 and C 28 in SWNTs.…”

Effects of pressure and temperature on sp3 fraction in diamondlike carbon materials

“…Wei et al 4 studied the deposition of energetic C 2 clusters on silicon and diamond surfaces and found that the mobility of surface atoms is enhanced at elevated energies in an earlier stage of deposition. Du et al 5 investigated the deposition of C 20 fullerenes on a diamond surface using the many-body Brenner bondorder potential. The deposited C 20 film showed high sta-bility even when the temperature was raised up to 1500 K. Jäger and Albe 6 simulated the ion beam deposition of DLC films using MD simulations and calculated the sp 3 fractions.…”