Modification in electrical transport with a change in geometry from a nanowire to a nanotube of copper: Effect of the extra surface

Abstract

We have studied the temperature-dependent (3-300 K) electrical resistance of metal nanowires and nanotubes of the same diameter with the specific aim to understand the changes in electrical transport brought about by a change in the geometry of a nanowire to a nanotube. Single crystalline nanowires and nanotubes of copper were synthesized by electrodeposition in nanoporous alumina templates. The temperature-dependent resistivity data have been analysed using the Bloch-Grüneisen function for the lattice contribution to resistivity, and the characteristic Debye temperature θ R was determined along with the residual resistivity ρ 0. Substantial size effects were observed in both the parameters ρ 0 and θ R, where the former is enhanced and the latter is suppressed from bulk to nanowires and further to nanotubes. It has been observed that the transport parameters in the nanotubes with wall thickness t are similar to those of a nanowire with diameter d, where d ≈ 2t in the specific size range used in this work. It is suggested that appreciable size effects in the electrical transport parameters occur due to the extra surface in the nanotube. In both nanotubes and nanowires, the single parameter that determines the size effect is the surface area to volume ratio. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.