Abstract
In this study, the photocatalytic activity of annealed TiN powders and films were examined to clarify the influence of annealing temperature and pressure on the photocatalytic properties under UV and visible light irradiation. TiN films were deposited on stainless steel and quartz substrates by DC magnetron sputtering, and annealed TiN powders were used as a reference material to confirm the effectiveness of TiN oxidation. TiN powders which were annealed at 873-1173K, showed obvious photocatalytic activity, under both UV and visible light irradiation. However, annealed TiN films on the stainless steel substrate showed low photocatalytic activity except for those annealed at 823K and 1.0kPa. This is because film annealed above 923 K consisted of a dominant rutile phase, and the film annealed at 1023K delaminated from the stainless substrate. For the quartz substrate, the dominant phase of the films annealed at 823 and 923 K was anatase, and all films remained completely on the substrate after annealing. In particular, the film which was annealed at 923K and 1.0kPa showed high photocatalytic activity both under UV and visible light irradiation. Thus, good photocatalytic activity can be obtained by annealing TiN with an appropriate temperature, pressure and substrate material.
