Assembly of TiO₂‐on‐Cu₂O Nanocubes with Narrow‐Band Cu₂O‐Induced Visible‐Light‐Enhanced Photocatalytic Activity

Abstract

Abstract Newly designed TiO 2 ‐on‐Cu 2 O nanocubes have been constructed as visible‐light‐driven photocatalysts with high efficiency by means of a facile self‐assembly approach at room temperature. In the resultant TiO 2 ‐on‐Cu 2 O nanocubes, the TiO 2 nanoparticles with a diameter of 6–8 nm show a well‐monodispersed distribution of the 200–300 nm‐sized Cu 2 O single‐crystal nanocubes, which can form sub‐monolayer, monolayer, and multilayer coverage through controlling the ratio of the two phases. In particular, the coupling of the wide‐bandgap semiconductor TiO 2 with narrow‐bandgap Cu 2 O can lead to the markedly enhanced high visible‐light photocatalytic activity in the TiO 2 ‐on‐Cu 2 O nanocomposite systems toward the photodegradation of rhodamine B, which is induced by the bandgap‐adjusting effect. This promising self‐assembly route can be extended to the preparation of other nanocomposite materials.