Photodeposition of Prussian blue films on TiO2:: Additive effect of methanol and influence of the TiO2 crystal form

The coupling of TiO2 and transition metal complexes is attempted with the aim of higher functionalization of the TiO2 photocatalyst, UV irradiation (lambda (ex) > 300 nm) of a TiO2 suspension containing equimolar aqueous solutions of FeCl3 and K-3[Fe(CN)(6)] forms uniform thin films of water-insoluble Prussian blue (PB, Fe-4(3+) [Fe-II(CN)(6)](3)) on the surface of TiO2 particles. The PB photodeposition is enhanced significantly by the addition of a small amount of CH3OH in both the rutile and anatase TiO2 systems. The activity of anatase TiO2 is greater than that of rutile in the presence of CH3OH (2.46 M) by a factor of 1.6 +/- 1.2, whereas the activities are comparable in the absence of CH3OH. These results are discussed on the basis of a proposed reaction mechanism. (C) 2001 Academic Press.