Design of macroporous TiO2 thin film photocatalysts with enhanced photofunctional properties

TiO2 thin films with uniform macropores were successfully prepared on quartz substrates by a dip-coating method using poly(methyl methacrylate) (PMMA) microspheres as a template. SEM observations revealed that the diameter of the macropores showed a good correspondence with the size of the PMMA microspheres. These thin films had anatase crystalline structures and maintained relatively high transparency. The degradation of organic pollutants such as 2-propanol and acetaldehyde under UV light was significantly enhanced by the construction of the macropores. It was also found that TiO2 thin films with macropores exhibited good photoinduced hydrophilicity after a short period of UV light irradiation, and a slow recovery of water contact angles in the dark as compared to those of non-porous TiO2 thin films.