Root growth of TiO2 nanorods by sputtering

The growth of TiO2 nanorods by a simple sputtering method is reported. Here we show that by sputtering of Ti target in argon–oxygen plasma it is possible to grow rutile core and anatase shell heterostructure TiO2 nanorods on gold (Au) coated Si(1 0 0) substrate without external heating. It seems that the nanorods grow because of the stress assisted diffusion of under-laying Au atoms into the TiO2 film followed by catalytic growth of the nanorods at the root.

► Low temperature growth of TiO2 nanorods by the sputtering method is reported.
► Nanorods grow because of the stress assisted diffusion of under-laying Au atoms into TiO2 film followed by root growth.
► Average density of nanorods increased with increasing Au layer thickness.
► TiO2 nanorods have a hetero-phase structure consisting of rutile core and anatase outer coating.