A facile method to form highly-ordered TiO2 nanotubes at a stable growth rate of 1000 nm min−1 under 60 V using an organic electrolyte for improved photovoltaic properties

Abstract

An effective method has been developed for the preparation of highly ordered TiO₂ nanotubes (TNTs) at a rapid growth rate. The idea is based on increasing the backside temperature of Ti foil during the anodization process, thereby enhancing the chemical reaction and ion mobility at the barrier layer. A combination of electropolishing pretreatment with the backside temperature increase showed a significant growth rate and hexagonal ordering improvement of TNTs. The most rapid growth rate obtained was approximately 1000 nm min⁻¹ under 60 V and at a backside temperature of 70 °C with an almost constant rate. The resulting TNTs were used as a photoanode in dye-sensitized solar cells in which the corresponding efficiency improved up to about 40% compared with TNTs fabricated using a backside temperature of 20 °C.