Preparation Of Quinoline Group Modified SBA-15 Nanocomposites And The Study Of Its Fluorescent Properties

The preparation of organic-inorganic hybrid fluorescent nanomaterials for detection of metal ions is the main work in this study. And the work is been divided into three parts:1), In this study, highly ordered mesoporous silica material (SBA-15) functionalized with N-(quinoline-8-yl)-2-(3-triethoxysilyl-propylamino)-acetamide (QTPA) as an INH logic gate was reported. The functionalized mesoporous SBA-15 silica (QTPA-SBA-15) was characterized by Powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR),29Si/13C solid state NMR spectra, N2 adsorption/desorption and thermal gravimetric analysis (TGA). The characterizations data indicated that the organic ligand was successfully grafted into the mesopores of SBA-15. The fluorescent characterization revealed that this material showed excellent selectivity to Cu2+ over other cations even in trace amount. And also exhibited fluorescent enhancement behaviour for Zn2+ ion. Moreover, due to the fluorophore moiety presented in the channels of SBA-15, QTPA-SBA-15 can be considered as a selective fluorescent probe for Cu2+. The fluorescent changes of QTPA-SBA-15 upon the addition of cations (Cu2+, Zn2+ and Cd2+) is utilized as an INH logic gate at the molecular level, using Cu2+, Zn2+ and Cd2+ as chemical inputs species and the fluorescence intensity signal as output.2), Carbon nanotubes (CNTs) were covalently modified by fluorescence ligand, glycine-N-8-quinolylamide (GNQ) and formed a hybrid materials for the detection of metal ions. The anchoring to the surface of the CNTs was carried out by reacting the precursors with the carboxyl groups available in the surface of the support. The characterization results of the materials by elemental microanalysis, Fourier Transform Infrared spectroscopy (FTIR). Thermogravimetric analysis (TGA) and electron microscopy (TEM) unambiguously proved that covalent anchorage had occurred. Steady-state fluorescence emission studies showed that these materials present a highly sensitive and selective detection for Zn2+, and the sensitivity was down to 0.2μM. The Interference of Cu2+ could be masked by adding Na2S2O3. These results demonstrated the advantage of this carbon nanotube based fluorescent materials for detection of Zn2+, and also made it a potential candidate for ratiometric Zn2+ detection.3), A magnetic composite of multiwalls carbon nanotubes (MWNTs) decorated with Cobalt nanoparticles was synthesized successfully by a simple chemical precipitation and deoxidization method. The composite was analyzed by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The pattern of XRD indicated that MWNTs and Cobalt nanoparticles coexisted in the composite. The TEM images revealed that the Cobalt nanoparticles were distributed on the surface of the MWNTs, with the size ranging from 5 to 15 nm. The hysteresis loops of the decorated MWNTs were measured by a vibrating sample magnetometer (VSM), the ferromagnetic signature emerged with the saturated magnetization of 5.8 emu/g, and the coercive of 310 Oe.