الفهرس 
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Abstract
Thesis aims to synthesize iron(III)- based metal- organic framework which modified by different percentages of silver nanoparticles like 1 wt%, 3 wt%, 5 wt%, 7 wt% and 10 wt%. These composites used for many applications as adsorption of organic (dyes) and inorganic(heavy metals) pollutants, catalysis of some organic reactions and biological activities. Structural characterization of the prepared samples was determined using TEM, SEM, X‐ray and FTIR analysis. 1-For X‐ray diffraction patterns, Presence of peaks at 2θ = 5.8o, 6.7o, 9.5o, 11.6o and 14.6o which are characteristics of MILs-101 compounds, were indexed as111, 200, 220, 222 and 331 hkl, respectively which confirmed the octahedral structure of samples. Peaks of metallic silver are observed at 2θ =38o, 44.62o and 65.4o which indexed as (111), (200) and (220) planes, respectively indicating the improved crystallinity of the silver nanoparticles on Fe-MIL-101 surface and the intensity of these peaks increased by the increase of silver content. The interplanar spacing (d), lattice parameter (ao) and average crystalline size (D) were determined for Ag/Fe-MIL-101 and the results showed that the crystal size of particles increases with the increase in Ag content due to the silver nanoparticles agglomeration. 2- FT-IR analysis for Fe-MIL-101 showed a very broad peak at 3100-3600 cm-1 which is corresponding to O-H bond for carboxylic group in Fe-MIL-101. The absence of 1720- 1680 cm-1 peaks suggested a deprotonating of COOH as a complex of iron. The peak with slightly high relative intensity at around 1660 cm−1 is assigned to ν(C=O) which suggests the presence of a high amount of free carboxylic groups. The peak appeared at 545 cm-1 is due to the vibration of Fe-O bond. Comparing the peaks of Ag/Fe-MIL-101 with MILL-101 indicated that there is a chemical interaction between Ag nanoparticles and the carboxylate form of Fe-MIL-101.3- TEM images indicated that Fe-MIL-101 catalysts have a well- defined octahedral structure with particle size in the range of 50- 500 nm. TEM images for Ag/Fe-MIL-101 catalysts revealed that the silver nanoparticles are homogeneously distributed on Fe-MIL-101 surface. By increasing Ag content, the crystal size of silver nanoparticles increases due to the agglomeration of silver nanoparticles.
4- The SEM figures showed the octahedral shape of Fe-MIL-101 catalysts and the prepared samples crystal sizes are in (100-500 nm) range without any agglomeration. The SEM analysis of Ag/Fe-MIL-101 samples showed that the surface consists of a cluster of spherical bead-liked structure of silver nanoparticles together with the octahedral structure of Fe-MIL-101 sample. With the increase in Ag content, the crystal size of particles increases due to the agglomeration of silver nanoparticles. We found that, Fe-MIL-101 samples have the ability of cationic and anionic dyes as methylene blue and methyl orange. The optimum pH for removal of methylene blue and methyl orange is 10 and 4 respectively. 5%Ag/Fe-MIL-101 is the best percentage for lead and cadmium ions removal. The optimum pH for Pb2+ and Cd2+ is 4 and 5 respectively. With increasing the amount of silver on the surface, the adsorptive activity dereases due to agglomeration of silver nanoparticles. Also, 5% Ag/Fe-MIL-101 is the best percentage prepared for the catalysis of 2,4-dihydropyrimidinones and xanthene synthesis. With increasing the amount of silver on the surface, the conversion decreases as the active centers on catalyst surface are blocked. Ag/Fe-MIL-101 samples have biological activities as antibacterial,antifungal and antioxidant activities. The more effective sample for these activities is 5%Ag/Fe-MIL-101.