Visible Light Photoelectrochemical Properties of N-Doped TiO2 Nanorod Arrays from TiN

N-doped TiO2 nanorod arrays (NRAs) were prepared by annealing the TiN nanorod arrays (NRAs) which were deposited by using oblique angle deposition (OAD) technique. The TiN NRAs were annealed at 330 degrees C for different times (5, 15, 30, 60, and 120 min). The band gaps of annealed TiN NRAs (i.e., N-doped TiO2 NRAs) show a significant variance with annealing time, and can be controlled readily by varying annealing time. All of the N-doped TiO2 NRAs exhibit an enhancement in photocurrent intensity in visible light compared with that of pure TiO2 and TiN, and the one annealed for 15 min shows the maximum photocurrent intensity owning to the optimal N dopant concentration. The results show that the N-doped TiO2 NRAs, of which the band gap can be tuned easily, are a very promising material for application in photocatalysis.