Preparation And Photophysical Properties Of Chromophores Pillared Mg-Al-LDH

In the thesis, Ethyl Orange (EO-),4-aminoazobenzene-4-sulfonic anion(4A-4S-),4-Methoxyphenylacetic Acid (4-MAA-) and 2-Naphthalene Sulfonic Acid (2-NSA-) have been intercalated into the layered double hydroxide (LDH), [Mg0.66Al0.34(OH)2](CO3)0.17·0.67H2O And we have investigated the preparation condition,the structure and the photophysical properties of the obtained products,systematically.The host material(Mg-Al-CO3-LDH) was prepared by the method of coprecipitation, and Mg-Al-EO-LDH,Mg-Al-4A-4S-LDH Mg-Al-4-MAA-LDH and Mg-Al-2-NSA-LDH were obtained by the ion exchange method using the ethanediol as the dispersion medium. X-ray diffraction, infrared and thermogravimetry were applied to characterize the obtained compounds. The photophysical properties of the obtained compounds were investigated by UV-Vis absorption and fluorescence spectroscopy. And the guest molecular sizes and structures were studied using ab initio (HF/6-31G) method of Gaussion-03.The results indicate that the fluorescence intensity of Mg-Al-EO-LDH and Mg-Al-4A-4S-LDH changed, compared with those observed in the pure microcrystalline EO and 4A-4S, the fluorescence intensity of the samples containing only surface-exchanged EO or 4A-4S reduced because the charge transfer between EO or 4A-4S molecules was enhanced; The confinement of the pairs of chromophores,4-MAA and 2-NSA within the interlayer region of the host was in favor of guest-host interaction and guest-guest interaction, and that the pair of chromophores, 4-MAA and 2-NSA could give rise to energy transfer processes because of the characteristics of their excited states. It shows that the photophysical properties of intercalation and co-intercalation compounds would be used for a novel class of layered light energy storage and conversion materials.