| AVS 54th International Symposium | |
| Advanced Surface Engineering | Wednesday Sessions |
| Session SE-WeM |
| Session: | Photocatalytic Coatings |
| Presenter: | M.S. Wong, National Dong Hwa University, Taiwan |
| Authors: | C.W. Weng, National Dong Hwa University, Taiwan P.W. Chou, National Dong Hwa University, Taiwan K.K. Rao, National Dong Hwa University, Taiwan M.S. Wong, National Dong Hwa University, Taiwan |
| Correspondent: | Click to Email |
We adopted a combinatorial approach to develop a series of carbon-incorporated titania (TiOxCy) films titania films with composition spread up to 40 at.% of carbon. The films were deposited on silicon and quartz substrates by co-sputtering a metallic titanium target and a graphite target simultaneously onto a stationary long-strip of substrate in a gas mixture of argon and oxygen. The location of substrates in relation to targets and the power of targets are found to be very crucial for the desired result. As the carbon content increases, the film structure and crystallinity transform from anatase to amorphous-liked phase and its morphologies and microstructures change from rough surface of columnar grains to smooth surface of nanocomposite. The carbon is present both in the form of substituted Ti-C bonds in anatase grains as well as free graphitic along grain boundaries or in matrix. With increasing carbon content, the film optical absorption in visible region decreases first and then increase, while the film optical bandgap energy varies from 2.6 up to 3.2, and then descends to 2.5 eV. On photocatalysis under visible light, the film with about ~10% carbon exhibits the largest photoreduction of silver-ions to form Ag particles and nano-wires, while the film of the best anatase crystallinity with about 3 at% of carbon has the most degradation of methylene blue. The content and the nature of carbon as well as the titania crystallinity dominate the visible-light induced photocatalytic activity of the TiOxCy films.