Promises and Challenges in Photocatalysis

Abstract

Subtleties in the synthesis of materials can have a profound effect on the catalytic and photocatalytic properties of materials. Black TiO 2 nanotubes, demonstrating remarkable solar absorption, were synthesized using a stainless steel reactor. Using UVvis diffuse reflectance spectroscopy, XPS, EDS, ICP, and TEM, the change in electronic absorption of the TiO 2 nanotubes is explained by the discrete introduction of Cr concentrated particles from the stainless steel reactor. The black TiO 2 nanotubes displayed significant solar-driven photocatalytic activity with the photo-oxidation of acetaldehyde under visible light (λ > 450 nm). © 2011 American Chemical Society.