Novel porous TiO2 glass-ceramics with highly photocatalytic ability

A porous TiO2 glass-ceramics with high photo-oxidative activity was successfully obtained from the SiO2–Al2O3–B2O3–CaO–TiO2 glass system. Rutile-type TiO2 was observed in the crystallization temperature range of 973–1173 K. The band gap of the glass-ceramics coincided approximately with that of rutile-type TiO2. The photocatalytic activity of this glass-ceramics was about four times larger than that of a TiO2-coated photocatalyst fabricated by the sol–gel process. Furthermore, as this porous TiO2 glass-ceramics contained TiO2 in composition form, it could prevent peeling of the TiO2 from the substrate. As well, this glass-ceramics can be easily shaped into sheets, tubes, rods, etc.