酸化チタンの熱励起活性ラジカル生成を利用した不完全燃焼成分の酸化・分解

抄録

Active radical species are generated on thermally-excited titanium dioxide (TiO₂) under air conditions. Oxidation and decomposition of unburned compounds, such as CO and acetaldehyde, were investigated using this activation of TiO₂. The materials used were TiO₂ bead and TiO₂/SiO₂ composite bead. The supporting ratio of TiO₂ on the composite bead used was 14% or 20%. Oxidation of CO to CO₂ was 70% at 500 ℃ using TiO₂ bead, though that was about 20% using TiO₂/SiO₂ bead. Decomposition of acetaldehyde was over 90% at 300 ℃ using TiO₂ bead or TiO₂/SiO₂ bead. The existence of TiO₂ particles on the surface and in the nano-pore of silica would allow the effective decomposition of acetaldehyde. It was assumed that the thermally-excitation of TiO₂ was caused by the formation of lattice defect, that is oxygen defect, in TiO₂ under high temperature followed by the active radical generation.