Fabrication of nanoporous TiO2 hollow capsules using core-shell silica nanoparticle templates

We report on the fabrication of the nanoporous TiO2 hollow capsules using core-shell silica nanoparticle templates. The thickness of the capsules can be simply controlled by varying the amount of the TiO2 precursor. The resulting nanoporous capsules exhibited the high specific surface area and the large pore volume of 103-180 m2/g and 0.40-0.86 cm3/g, respectively. Photocatalytic activity of the TiO2 hollow capsules was also investigated and compared to that of the commercial TiO2 nanoparticles.