Implications and discussion

Control of the LCD systems synthesis process completeness performed by fixing constant temperature of mesophase transition, as a result, we got isotropic liquid in the whole volume of the sample.

Exploring LCD system textures, we found out that one system has a lamellar mesophase (C12EO14/H2O), and two others have hexagonal one (C12EO10/H2O, C12EO9/H2O).

System were obtained with silicate matrix based on two different precursors - vinyl trimethoxysilane and phenyl triethoxysilane by sol-gel technology. During the synthesis of the silicate matrix, molar ratios, aging time and drying time were the most important characteristics, so they were experimentally optimized (Table 1).

Table 1. Controlled parameters during the sol-gel synthesis.

* Published data.

After the admission of silicate into LCD, synthesized systems were investigated by polarized light. As in the original liquid crystal systems, appropriate texture observed that to characterize the supramolecular organization of the molecules in the mesophase.

Nanocomposite films were prepared by the method of spin coating. This method allows control of the film thickness, but this is a uniform distribution of the sample on the substrate.

Annealed porous films placed in a solution of the complex tris [1,3-diphenyl-1,3-propanedione] - [2,2 '-bipyridyl] Europium Eu (DBM) 3bpy in toluene for adsorption equation for 24 hours. Then the samples were washed in toluene to remove the surfactant and water out of the surface and dried to remove the solvent [10]. After the process, the systems under study were examined by fluorescent spectroscopy (Fig. 1).

Figure 1 - The luminescence spectrum and kinetics of luminescence system SiO2/C12EO4/Eu (DBM) 3bpy.

Lack of main energy transition signal splitting looks as shown: 5D0 → 7F1, 5D0 → 7F2 and 5D0 → 7F3 and indicates a low symmetry of the ligand environment of ion Eu³⁺, which in principle expected in lyotropic systems containing a large amount of solvent. Small ratio of the peak areas of transitions 5D0 → 7F2 and 5D0 → 7F1 equal to 5.9 indicates a weak energy transfer from the ligand to the ion.

In films obtained on the glass, there is a uniform and orderly arrangement of the complex Eu (DBM) 3bpy silicate and SiO2, which increases the luminescence lifetime (Fig. 2).
Found out that oriented systems compared to disordered systems have more intense photoluminescence.

It should be emphasized the role of the orientation of mesophases as a necessary step in the organization of a liquid crystal template. Orientation mesophases switches from supramolecular organization in the domains of the sample to streamline the entire volume, which is especially important for the practical design of new functional materials when used in molecular electronics and laser optics.

a) b)

Figure 2 - a) The ratio of the peak intensities of 5D0 → 7F2/5D0 → 7F1; b) Survival Time the glow luminescent complexes.

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