Quartz glass slides were used as substrates.
Before the deposition, substrates were ultrasonically
cleaned in dilute HNO3, acetone and absolute
ethanol for 30 min, respectively. Finally, they were
thoroughly rinsed with water. TiO2 thin films were
deposited on substrates by a dip-coating process at
room temperature. Substrates were immersed into
the TiO2 sol for 10min. Upon withdrawing from
the sol, the substrates were dried in electric furnace
in air at 60 1C for 20 min. Afterward, the
substrates were ultrasonically rinsed with water
for 10 min and then dried at 60 1C for 60 min.
Films so obtained were well adhered. TiO2 layers
on substrates could be thickened by means of
consecutive dip-coating processes. In such cases,
substrates were only ultrasonically rinsed with
water and dried at 60 1C for 60 min at the end of
the whole deposition process.
PrOH and n-butyl alcohol were removed from the
solution in a rotatory evaporator under vacuum.