Mechanism of aerobic visible light formic acid oxidation catalyzed by poly(tri-s-triazine) modified titania

作者:Mitoraj Dariusz; Beranek Radim; Kisch Horst*
来源:Photochemical and Photobiological Sciences, 2010, 9(1): 31-38.
DOI:10.1039/b9pp00052f

摘要

Visible light aerial oxidation of formic acid catalyzed by N/C-modified titania (TiO(2)-N,C) is investigated by wavelength-dependent photocatalytic and photoelectrochemical experiments in the presence of oxygen, tetranitromethane, and methylviologen as electron acceptors. The title reaction is shown to proceed both through oxidative and reductive primary processes. Contrary to the urea-derived (TiO(2)-N,C), so-called "N-doped" titania (TiO(2)-N) as prepared from ammonia is inactive. In accord with photocurrent action spectra of corresponding powder electrodes, this different activity of the two photocatalysts is traced back to the different chemical nature of the reactive holes localized at the modifier. Hole stabilization by delocalization within an extended poly(tri-s-triazine) network of TiO(2)-N,C is proposed to render recombination with conduction band electrons less probable than in TiO(2)-N.

  • 出版日期2010