Phenol degradation on the surface of mesoporous TiO₂ particles via ligand-to-metal charge transfer under visible light irradiation

Degradation behaviors of phenol from aqueous solution under the blue light irradiation were studied using a series of sol–gel prepared TiO₂ particles exhibiting different blue light absorbing abilities. The phenol degradation under the blue light irradiation was most pronounced in the presence of TiO₂ sample exhibiting the lowest blue light absorbing ability among the samples, showing no correlations between phenol degradation and light absorbing ability of TiO₂ particles. UV-DRS analysis and scavenging experiments revealed that phenol degradation under visible light irradiation can be majorly proceed via the light absorption by the ligand-to-metal-charge-transfer (LMCT).