Mesoporous titania with high crystallinity during synthesis by dual template system as an efficient photocatalyst

The mesoporous titania, designated MS-TiO2 was successfully prepared via a new combination of pluronic P123 and poly ethylene glycol templates and acetic acid as the hydrolytic retardant with extremely high crystallinity achieved during synthesis process. MS-TiO2 has remarkable thermal stability, biporous mesostructure and superior photocatalytical activity for phenol degradation and mineralization as compared to mesoporous TiO2 prepared using single template systems. The anatase–rutile phase transformation of the MS-TiO2 was not observed up to 800 °C. The mesoscale order of MS-TiO2 was retained after thermal treatment up to 450 °C as confirmed by low angle X-ray diffraction and transmission electron microscopy analyses. It maintained its pore properties at high temperature of 700 °C with a significant pore size 10.4 nm and pore volume 0.11 cm3/g. MS-TiO2 has biporous mesostructure with the small mesopore of 5.5 nm and the large mesopore of 8.7 nm in mean pore diameters. The MS-TiO2 showed higher photocatalytic activity for phenol degradation than mesoporous titania prepared using single templates and standard system of Degussa P25. The remarkably high catalytic activity of the MS-TiO2 is attributed to its high crystallinity and biporous mesostructure. The phenol mineralization was confirmed using high performance liquid chromatography and total organic carbon analyses.

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► Highly crystalline mesoporous titania in as prepared form is achieved by a new combination of dual-template system of triblock copolymer (P123) and poly ethylene glycol (PEG).
► The moment of anatase formation during the synthesis depends on both medium and type of surfactants used.
► This combination provides more hydrophobic contrast than single template system resulting in the thicker anatase walls which gives higher thermal stability.
► Excellent photocatalytic abilities for phenol degradation and mineralization as compared to Degussa P25 and mesoporous titania prepared by single templates.