Hierarchical ordered macro/mesoporous titania with a highly interconnected porous structure for efficient photocatalysis

In this study, a 3-dimensional interconnected hierarchical ordered macro/mesoporous titania (HOPT) with thin walls, crystalline framework, large cavities (∼420 nm), uniform mesopores (3.7 nm) and high surface area (177 m² g^-1) was synthesized through a facile bi-template interface-directed deposition method using poly(propylene oxide)-block-poly(ethylene oxide)-block-poly(propylene oxide) (Pluronic P123) triblock polymer as a soft template and structure directing agent, titanium isopropoxide (TIPO) as a titania source and 3-dimensional ordered macroporous carbon (3DOMC) as the hard template and the nanoreactor. This was followed with a two-step thermal treatment in nitrogen and air. Under simulated sunlight irradiation at room temperature, the HOPT shows an ultrahigh photocatalytic activity for the degradation of Rhodamine B (RhB) with a fast reaction rate that is three times higher than commercial titania nanoparticles (P25).