Mesoporous films of TiO(2) as efficient photocatalysts for the purification of water.
Variably thick mesoporous TiO(2) films were prepared by alternately dip- and spray-coating using sol containing titanium(IV) alkoxide, concentrated HCl and suitable block-copolymer as a structure directing agent. The film thickness was controlled by varying the number of deposited layers. Their porosity was homogeneous: surface area and pore volume increased linearly with increasing number of deposited layers. Photoactivity of the films was tested employing photocatalytic degradation of 10(-4) M 4-chlorophenol in a 60 mL photoreactor under UV irradiation at 365 nm. The incident light intensity was 1 mW cm(-2). The degradation rate constants increased with increasing number of layers, proportional to their absorbances. However, the progressive improvement of the photocatalytic performance slightly decreased with the increasing number of layers. The spray-coating layers exhibited lower photocatalytic performance due to their smaller thicknesses.
J. Heyrovský Institute of Physical Chemistry of AS CR, v.v.i., Dolejškova 3, 182 23, Prague 8, Czech Republic. jiri.rathousky@jh-inst.cas.cz
Jiří
J
Rathouský
Vít
V
Kalousek
Michal
M
Kolář
Jaromír
J
Jirkovský
D002384:Catalysis; D002733:Chlorophenols / Q000737:chemistry; D010777:Photochemistry; D016062:Porosity; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014867:Water / Q000032:analysis; D018508:Water Purification / Q000379:methods*
D002733:Chlorophenols; D014867:Water; C009495:titanium dioxide; C029107:4-chlorophenol; D014025:Titanium