Inverse Opal Structure of Nitrogen-Doped Titanium Oxide with Enhanced Visible-Light Photocatalytic Activity

Nitrogen-doped titanium oxide inverse opal structure was synthesized to combine both chemical and physical modifications on n -TiO₂ by the polystyrene sphere self-assembly followed by a sol–gel process. Enhanced visible-light absorption and subsequently enhanced photodegradation efficiency were observed in this unique structure, which can be attributed to both nitrogen-doping effect and inverse opal structure effect. Our work suggests that the coupling of photonic band gap structure with photocatalytic materials is a promising approach to achieve maximum enhancement for various photocatalytic materials, especially for environmental applications and solar cell devices.