Ultrastable TiO2 foams derived macro-/meso-porous material and its photocatalytic activity

Particles-stabilized TiO2 icecream-like foam was prepared by a versatile mechanical stirring method. It showed ultrastable state in air for several days. After calcining the wet foam, an open honeycomb-like structure with macro-/meso-porosity was formed. The photocatalytic characters of as-prepared macro-/meso-porous materials were detected, and the results indicated that the catalytic activity is increased about 120% compared to that of nanoparticles with acetaldehyde as a probe. Composite porous structure provided open pathways for high accessibility of molecular transport, increased surface area for more active center, and enhanced light-collection efficiency due to the inner light scattering effect, resulting in better photocatalytic activity. (C) 2008 Elsevier Inc. All rights reserved.