271
Nanofibers, Nanowires, or Nanorods
Glass, optical, carbon, titanate, and woven cloth fibers have also been studied as
support materials in the photooxidation of various organic contaminants for water
purification [263]. Most of these fibers have a protruded rod shape or longitudinal
morphology. Using the nanofibers, nanowires, or nanorods, mass transfer limitation can be resolved by their thin longitudinal morphology. The use of less durable
immobilizer fibers (e.g., of glass or woven cloths), however, may lead to a low
durability as the deposited anatase crystals might wear off, resulting in a loss of
photoactivity over reaction time. Such immobilizer fibers also increase pressure
drop in the reactor system. On the contrary, a good benefit of nanofibers with commercial success is that they can be fabricated into MF, ultrafiltration (UF), and
Fig. 13.5 Nanocrystal of
TiO 2 deposited on clay
materials by SEM imaging.
(a) 10 μm resolution; (b)
3 μm resolution
Recent Developments in Photocatalytic Water Treatment Technology