In situ organofunctionalized silica

The in situ organofunctionalized silica complexes were prepared by reacting the eta-modified sihca with an ethanolic solution of EUCI3. Schematic representations of the in situ synthesized complexes are shown in Fig. 3.6. 

Figure 3.6 Schematic representation of eta (a) and eta—phen (b) of in situ organofunctionalized silica europium complexes.

The emission spectra for free and in situ organofunctionalized silica prepared complexes are shown in Figs. 3.9 and 3.10. As can be seen from Figs. 3.9a and 3.9b,... 

The experimental results indicate that the substitution of water molecules by a phen molecule into the coordination sphere of a Eu-eta complex enhances the luminescence intensity due to the lowering of the number of OH oscillators (which suppress the luminescence), as well as the ability of phen to act as a good chromo-phor. Furthermore, the in situ organofunctionalized silica-eta complex exhibits an optimization of optical properties, in comparison with the free complex, mainly an enhancement of the emission intensity. The experimental parameters show that the dynamic coupling mechanism is predominant. 

It has been shown that organofunctionalized silica surfaces further modified with in situ synthesized copper complexes can be used to produce new stationary phases for HPLC [4]. The immobilized copper complexes provide new sites in the stationary phase that can interact strongly with basic organic compounds. A test mixture of compounds such as benzene, toluene, naphthalene, anthracene, pyrene, and nitrobenzene shows that the presence of copper ion complexes on the modified surface strongly affects the retention factor (fe) of the stationary phases. 

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