Bactericidal effect of an energy storage TiO2–WO3 photocatalyst in dark

• DOI: 10.1016/j.elecom.2003.07.003
• Publication Date: 2003-09-12T03:46:55Z
• Authors: Tetsu Tatsuma; Shuichi Takeda; Shuichi Saitoh; Yoshihisa Ohko; Akira Fujishima
• Keywords: Ultraviolet

TiO2–WO3 composite photocatalyst films can be charged with reductive energy by irradiation with ultraviolet (UV) light. The photo-charged film exhibited a moderate bactericidal effect on Escherichia coli during 6-h exposure in dark. On the other hand, the pre-discharged film exhibited no significant bactericidal effect. The moderate bactericidal effect may restrain bacteria from increasing during the night, and the survived bacteria may be killed by TiO2 due to its strong bactericidal effect in the next day. The photo-charged film generated H2O2 by reducing oxygen. The bactericidal effect of the photo-charged film was close to that of H2O2 of the generated amount. Thus, the bactericidal effect of the photo-charged TiO2–WO3 film can be explained chiefly in terms of the generated H2O2.