الفهرس 
Supramolecular chemistry
Cupper(I), Nickel(II) and Cobalt(II) as MOFsOnly 14 pages are availabe for public view
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Abstract
mary The current study is concerned with syntheses, characterization and catalytic applications of three metal organic frameworks (MOFs) and their nanosized particles; MOF1 {[Cu6(CN)7(C6H12N4)2(OH3)]}, nanosized1\ {[Cu6(CN)7(C6H12N4)2(OH3)]}, MOF2 {[Ni2(EN)8(NCS)4]}, nanosized2\ {[Ni2(EN)8(NCS)4]}, MOF3 {[Co (EIN)4(NCS)2]} and nanosized3\ {[Co (EIN)4(NCS)2]}, based on transition metals (CuI, NiII and CoII) and bridging heterocyclic ligands [hexa-methylene tetra-amine (hmt), ethyl nicotinate (EN) and ethyl isonicotinate (EIN)] in addition to CN and SCN ions as pseudo-halides co-ligands in the presence of trimethyltin chloride [(CH3)3SnCl]. The structures of these MOFs are characterized by single crystal X-ray diffraction, spectroscopic methods, powder X-ray diffraction (PXRD), transmission electron microscope (TEM) and scanning electron microscopy (SEM) analysis. The catalytic and photo-catalytic of MOFs 1-3 and their nanosized samples in presence of H2O2 are investigated. The kinetic data indicate that MOFs 1-3 and the nanosized 1\-3\ are very effective catalysts, especially nanosized 1\-3\ for degradation of CR, MV, MB and IC dyes while irradiation enhances significantly the rate of degradation. Disodium salt of terephethalic acid photoluminescence probing technology was carried out to detect the reactive oxygen species. Moreover, the mechanism of degradation of CR and IC dyes was also discussed. Also, the photoluminescence sensing measurements of MOF2 proved that it can be used as photo-chemical devices for selective quantitative determination of metal ions and explosives. This thesis consists of three chapters: - Chapter (I): This chapter includes a general introduction and literature survey on the MOFs of transition metals and organic compounds. This chapter also contains some concepts of supramolecular chemistry, metalorganic frameworks (MOFs), coordination polymers, nanostructured materials, synthesis of MOFs, types, identification of MOFs, applications of the MOFs. Chapter (II): This chapter includes the details of experimental procedures such as the materials and the instruments which can be used for different measurements. Additionally, it includes the techniques of preparation and characterization of the metal organic frameworks (MOFs) 1-3 and their nanosized 1\-3\. Furthermore, this chapter contains the experimental techniques of photoluminescence sensing measurements of MOF2. Chapter (III): This chapter includes the results and discussion of the experimental data. The structures of MOFs are investigated by different characterization techniques such as single crystal X-ray diffraction, powder X-ray diffraction (PXRD), infrared spectra (IR), absorption and emission spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET). This chapter is divided into three parts. Part I: Consists of the results and discussion of {[Cu6(CN)7(C6H12N4)2(OH3)]}; MOF1 and its catalytic activity. The single crystal X-ray diffraction of MOF1 indicates that all the copper atoms exhibit pseudo-tetrahedral configuration (PT-4) which are crystallography and chemically different. The structure of 1 extends to create complex network which contains four fused rings; two identical {[(Cu)2μ3– (CN)2](hmt)(CN)}rings, one {[(Cu)2μ3–(CN)2]4(hmt)4} ring and one {[(Cu)2μ3–(CN)2]2Cu4(hmt)} ring. The main feature in the structure of 1 is the many rhombic bifurcated [(Cu)2μ3–(CN)2] motifs which exhibit cuprophilic interaction. The [(Cu)2μ3–(CN)2] motifs expand the structure of 1 three dimensionally constructing eight fused cyclic rings accommodating two hmt ligands. The structure of the nanosized1\ is clarified using PXRD, spectroscopic methods and elemental analysis. PXRD indicates that MOF1 and MOF1\ are iso-structure due to the similarity of the simulated PXRD pattern and the experimental PXRD patterns. Also, the FT‐IR spectra of the MOF1 and nanosized1\ are identical containing the same bands. The electronic absorption spectrum of MOF1 exhibits three absorption bands at 255, 305 and 312 nm and the emission spectrum of MOF1 displays four bands centered at 330, 350, 410 and 475 nm. The morphology of the nanosized1\ is similar to that of MOF1 obtained by self-assembly method, the SEM images of the MOF1 support the rod shape observed in TEM images and the TEM images of the nanosized1\ indicate that it has good nanostructure than that of MOF1. The textural properties of MOF1 and nanosized1\ are determined from the N2 adsorption –desorption isotherms at liquid nitrogen temperature. The specific surface area, the mean pore diameter and total pore volume are calculated according to Brunner-Emmett- Teller (BET) method. Studying the catalytic and photocatalytic effect of MOF1 and nanosized1\ can be considered as an important goal. CR, MV and MB are selected as target pollutants for degradation experiments to evaluate the catalytic performance of MOF1 and nanosized1\ in the presence of H2O2. The control experiments under the uniform conditions using, only H2O2 or UV-light or ultrasonic irradiation, without catalyst illustrate that there is noteworthy decrease of the characteristic absorption even at long time but in the presence of H2O2 and MOF1 or MOF1\ catalyst exhibiting highly degradation effect. The obviously increased photo catalytic mineralization rate of the dyes indicates that the nanosized1\ is more energetic for the degradation of the tested dyes under UV-light or ultrasonic irradiation (D% =98.05 within 6 min (CR) dye, D%= 99.84 within 15 min (MV) dye and D% = 98.83 within 13 min (MB) dye). The kinetic studies are carried out under pseudo-first order conditions with respect to the [dye]. The catalyst MOF1 kept up its catalytic activity for at least two cycles of the dye oxidation under normal conditions. Also, the degradation products stayed in solution are checked by FT-IR and absorption spectroscopy as well as chemical methods after complete dye mineralization by the catalyst 1 under normal condition which support complete degradation of the tested dyes. Effect of operational parameters on CR dye degradation was carried to optimize design of an existing process. Mechanism of degradation using different scavenger techniques was proposed and discussed. The system can produce hydroxyl radicals, as confirmed by photoluminescence probing technology.