S. Takenaka et al., Preparation of porous titania film from precursor solution containing titanium alkoxide and stearic acid, J CERAM S J, 109(8), 2001, pp. 712-714
A porous titania film was prepared on a glass substrate by a spin-coating t
echnique from the precursor solution containing titanium tetraisopropoxide
and stearic acid. Stearic acid formed a 2 : 2 complex with titanium in the
dried film, and the complex melted before decomposition. Before the coating
of the precursor solution, methylsilane precoating on the hydrophilic glas
s surface was effective in preparing a uniform film because of hydrophobici
ty of the complex melt. The resultant film was transparent and composed of
anatase after heating at 500 degreesC. Micrometer-scale rough surface with
aggregates of secondary particles composed of primary crystallites was obse
rved in the film, and mesopores seem to be located at the inter-crystallite
s. It is probable that decomposition of stearic acid and aggregation of ana
tase crystallites occur simultaneously to provide the porous structure duri
ng heating.