Titanium dioxide (TiO2) doped with sulfur (S) was synthesized by oxidation annealing of titanium disulfide (TiS2). According to the x-ray diffraction patterns, TiS2 turned into anatase TiO2 when annealed at 600°C. The residual S atoms occupied O-atom sites in TiO2 to form TiS bonds. The S doping caused the absorption edge of TiO2 to be shifted into the lower-energy region. Based on the theoretical analyses using ab initio band calculations, mixing of the S3p states with the valence band was found to contribute to the band gap narrowing.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)