Synthesis of titanium-containing MCM-41 mesoporous molecular sieves in the presence of zinc phthalocyanine and rhodamine B

The synthesis of titanium-containing MCM-41 mesoporous molecular sieves in the presence of dye molecules results in a well developed hexagonal structure if the powder dye is dissolved in a surfactant solution. These materials contain titanium species in tetrahedral and octahedral coordinations simultaneously, indicated (i) by absorption bands at 960 cm(-1) in the infrared and Raman spectra, which are assigned to titanium in a silica network, and (ii) by bands in the Raman spectra which are characteristic for rutile. The flat slope of the red flank of the UV bands below 300 MI points also to the presence of fourfold and sixfold coordinated titanium. Zinc phthalocyanine is proposed to be embedded in the micelles as a monomer predominantly, whereas rhodamine B is assumed to be exclusively located outside the micelles or at the external surface as aggregates.