Nanopipes in In_2 O_3 nanorods grown by a thermal treatment

Abstract

In_2O_3 nanorods have been grown by a catalyst free evaporation-deposition method. Transmission electron microscopy (TEM) investigations reveal that the rods contain tubular cavities, herein referred to as "nanopipes", along the total length of the nanorods. The nanopipe diameters are constant along the nanorod axis and appear to be independent of the nanorod thickness. In most of the investigated In_2O_3 nanorods, these nanopipes are centered within the nanorod. An average nanopipe diameter of (18.5 +/- 0.7) nm has been determined from the TEM observations. Extended thermal treatments lead to nanorods with more complex morphologies, roughened interfaces, and formation of voids. The possibility that the nanopipes are related with a growth mechanism involving a dislocation along the growth axis is discussed.