A phthalocyanine covalently bonded to a silica network by a sol–gel process

The preparation and properties of a phthalocyaninosilica, where the phthalocyanine is covalently bonded to an inorganic network, are described. The synthesis consists of the reaction between tetrachlorosulfonylphthalocyanine (PcSO2Cl) and 3-aminopropyltriethoxysilane (APTES) under reflux in dry dichloroethane. After that, ethanol, tetraethoxysilane, water and 1 M HCl or 1 M NH4OH were added to the reaction mixture. The properties of this new material were determined by thermal analysis (TGA/DTA), absorption, luminescence and infrared spectroscopy. The absorption spectra confirmed the presence of the phthalocyanine in the material. The emission spectra of the phthalocyanine and phthalocyaninosilica were measured to verify the structure of the phthalocyanine after its incorporation into the silica. The thermal analysis shows the presence and the retention of the thermal stability of phthalocyanine in the matrix. The resulting materials are presented as blue films and monoliths with optical quality.