Decomposition of gaseous toluene on thermally-excited titanium dioxide and its ESR study under high temperatures

Decomposition of gaseous toluene on thermally-excited activated titanium dioxide (TiO₂) was investigated using a simple flow system. The decomposition of toluene on the TiO₂ bead was 92% at 400 °C. The irregular phenomena in the toluene decomposition at around 300 °C seemed to be due to the coloration of the TiO₂ bead. Electron spin resonance (ESR) measurement at high temperatures was carried out using the heating unit. Since the g-value of the signal was 1.996, the existence of Ti³⁺ in TiO₂ material was confirmed. That is, oxygen vacancy generated by thermally-excitation of TiO₂, and the reaction activity of the TiO₂ bead for gaseous toluene must be due to spins on the material.