Single crystalline TiO2 nanowires have been successfully grown on alumina substrates using a high-frequency
(350 KHz) dielectric heater at 1050 1C by a two-step of thermal evaporation method without using any catalyst. The
first step is to form the high surface energy TiO2 seeds on the low surface energy alumina substrates. The second step is
to grow the single crystalline TiO2 nanowires on the alumina substrates by the vapor–solid (VS) mechanism.