Encapsulation of iron phthalocyanine in sol-gel materials

Iron tetrasulfophthalocyanine (FePcS) was incorporated in sol-gel materials directly during the synthesis of hydrophobic and hydrophilic sol-gel materials by three different methods. The BET surface areas and pore size distributions of the prepared materials were determined from N-2 adsorption isotherms at 77 K. The structures of the gels were investigated by Si-29 NMR. The texture and the structure of the sol-gel materials was shown to depend on the preparation method. The incorporation of FePcS in the sol-gel materials was checked by diffuse reflectance UV-VIS spectroscopy. The band broadening of the incorporated FePcS molecules suggests that the complex is incorporated in dimeric or oligomeric forms. The presence of FePcS modified the structure of the gels resulting in the formation of a more polymeric, less extensively crosslinked silica gel network. The catalytic performance of these sol-gel materials containing the FePcS complex was tested in the oxidation of 2-methylnaphthalene and 2,3,6-trimethylphenol. (C) 2001 Elsevier Science B.V. All rights reserved.