title: Effect of annealing environments on self-organized TiO2 nanotubes for efficient photocatalytic applications.
abstract: In the present study, amorphous titanium dioxide (TiO2) nanotubes were synthesized by one-step anodization technique and subsequently annealed in different environments to investigate the effect of annealing atmospheres on the formation of different crystalline phases. X-ray Diffraction (XRD) patterns clearly showed the presence of anatase TiO2 phase with various crystallite sizes. The samples annealed in oxygen and air atmospheres at 500 degrees C showed a dominant anatase phase and a small amount of rutile phase, on the other hand, the samples annealed in nitrogen and argon atmospheres and in a vacuum at 500 degrees C contained the anatase phase only. XPS analysis of the samples showed a broadening in the binding energy curves with respect to variation in annealing atmosphere, confirming the variation in surface defects, which in turn affect photocatalytic degradation. The vacuum-annealed sample showed superior photocatalytic degradation efficiency as it had relatively higher pseudo-first order rate constants (k) of 0.009/min.
authors: Department of Materials Science and Engineering, Korea University, Seoul 136-701, Korea.
authors: Rajeshkumar Shankar
authors: RS
authors: Hyam
authors: Jongseok
authors: J
authors: Lee
authors: Eunju
authors: E
authors: Cho
authors: Jeehyeong
authors: J
authors: Khim
authors: Haigun
authors: H
authors: Lee