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Narrowing the band gap and increasing the photodegradation efficiency of TiO₂-based photocatalysts are very important for their wide application in environment-related fields such as photocatalytic degradation of toxic pollutants in wastewater. Herein, a three-dimensionally ordered macroporous Pt-loaded TiO₂ photocatalyst (3DOM Pt/TiO₂) has been successfully synthesized using a facile colloidal crystal-template method. The resultant composite combines several morphological/structural advantages, including uniform 3D ordered macroporous skeletons, high crystallinity, large porosity and an internal electric field formed at Pt/TiO₂ interfaces. These unique features enable the 3DOM Pt/TiO₂ to possess a large surface for photocatalytic reactions and fast diffusion for mass transfer of reactants as well as efficient suppression of recombination for photogenerated electron-hole pairs in TiO₂. Thus, the 3DOM Pt/TiO₂ exhibits significantly enhanced photocatalytic activity. Typically, 88% of RhB can be degraded over the 3DOM Pt/TiO₂ photocatalyst under visible light irradiation (λ ≥ 420 nm) within 100 min, much higher than that of the commercial TiO₂ nanoparticles (only 37%). The underlying mechanism for the enhanced photocatalytic activity of 3DOM Pt/TiO₂ has been further analyzed based on energy band theory and ascribed to the formation of Schottky-type Pt/TiO₂ junctions. The proposed method herein can provide new references for further improving the photocatalytic efficiency of other photocatalysts via rational structural/morphological engineering.