The cluster formation of silver adatoms on carbon nanotubes (CNTs) is investigated to infer the curvature effect on surface diffusion. By analyzing the cluster density as a function of the deposition time t for different diameters dc of CNTs, we obtain the scaling form for describing the curvature effect on surface diffusion in the first-order approximation. We find that the curvature effect on the surface diffusion can well be described by using the relation between the deposition time t and the scaled deposition time τ in the form of τ∼t dc -z, with z being the exponent characterizing geometric properties of CNTs and the nanotube helicity. The value of z for the armchair-type CNT is larger than those for the zig-zag type and the chiral-type CNTs. The scaling form is further demonstrated and verified by numerical simulations, and is explained by the two-dimensional random walk model. Our study may provide a potential application of determining the armchair-type single-wall CNT from measuring the value of z.
|期刊||Physical Review B - Condensed Matter and Materials Physics|
|出版狀態||已出版 - 2006|