In-Situ Nitrogen Doping of the TiO ₂ Photocatalyst Deposited by PEALD for Visible Light Activity

In this paper, an N-doped titanium oxide (TiO ₂ ) photocatalyst is deposited by a plasma-enhanced atomic layer deposition (PEALD) system through the in-situ doping method. X-ray photoelectron spectroscopy (XPS) analysis indicates that substitutional nitrogen atoms (∼395.9 eV) with 1 atom% are effectively doped into TiO ₂ films. UV-VIS spectrometry shows that the in-situ nitrogen doping method indeed enhances the visible-activity of TiO 2 films in the 425-550 nm range, and the results of the performance tests of the N-doped TiO ₂ films also imply that the photocatalysis activity is improved by in-situ doping. The in-situ doping mechanism of the N-doped TiO ₂ film is suggested according to the XPS results and the typical atomic layer deposition process.