Stable bidentate coordination sulfated TiO2 for highly durable photocatalytic degradation of gaseous acetone

Sulfated TiO2 was considered to be one of the most promising photocatalysts for enhancing photodegradation of organic pollutants. Different sulfate coordinated TiO2 catalysts were fabricated for photocatalytic degradation of acetone. The commercial Degussa TiO2 treated with concentrated H2SO4 showed a great improvement of acetone removal of 85% at continuous flow reaction and no deactivation occurred with prolonging reaction time, as comparison that parent TiO2 had a low removal rate and rapid deactivation for acetone degradation. Two kinds of SO42- coordination on TiO2 were revealed dependent on the treated H2SO4 concentration. Stable bidentate coordination SO42- acted as a trap center of photogenerated electrons for photocatalytic degradation of acetone. However, loose monodentate coordination SO42- on TiO2 surface was liable to open bridging S-OH-Ti group, resulting in the deactivation of photocatalytic acetone degradation. This work provided insight into the relationship between sulfate structure and its photocatalytic performance for sulfated TiO2 photocatalyst.

Automated summary

Sulfated TiO2 is a promising photocatalyst for enhancing the photodegradation of organic pollutants. Different sulfate coordinated TiO2 catalysts were fabricated for the degradation of acetone. Treatment of Degussa TiO2 with concentrated H2SO4 showed significant improvement in acetone removal, while the parent TiO2 had low removal rate and rapid deactivation. The study revealed two forms of SO42- coordination on TiO2, with stable bidentate coordination acting as a trap center and loose monodentate coordination leading to deactivation.