Sharif Digital Repository

In first part Mesoporous silica (SBA-15) was synthesized by template synthesis method and the surface of SBA-15 was functionalized with 3-glycidoxypropyltrimethoxysilane and 5-Phenyl-1H-tetrazole. Palladium nanoparticles were immobilized on the aforementioned mesoporous support. Characterization of catalyst regarding to its structure, morphology and other parameters was investigated by physiochemical analysis such as XRD, SEM, TEM, and TGA. This heterogeneous catalyst has high capability in reduction of nitrobenzenes and selective oxidation of primary alcohols which respectively gain aminoarenes and benzaldehydes in high yields. Reduction and oxidation reactions are done in water as a green... 

This present work is an introduction of a new electrochemical sensor toward the determination of biomolecule. A simple electrodeposition method was employed to construct a thin film modifier of palladium–gold nanoparticles (Pd–AuNPs) decorated multi-walled carbon nanotube (MWCNT) on the surface of glassy carbon electrode (GCE). Morphological characterization of the modified electrode was performed by the scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and cyclic voltammetry (CV) techniques. This nanostructured film modified electrode effectively exhibited enhanced properties for the detection of ceftazidime (CFZ). The effects of various experimental variables such... 

Hexavalent chromium ions (Cr(VI)) is one of the most dangerous heavy ions for the environment, humans and other living organisms. Hence, finding new ways to determine and reduction to the much less toxic trivalent chromium (Cr(III)) is highly important. In this thesis, electrochemical and photoelectrochemical methods have been employed for the direct detection and reduction of Cr (VI). For this purpose, the indium tin oxide (ITO) electrode decorated with gold-palladium bimetallic nanoparticles (AuPd) was used for the determination and reduction of Cr(VI) via electrochemical route. These AuPd decorated electrodes exhibited a wide linear concentration range of 0.001-100 µM, a very low... 

In this research, synthesis of new heterogeneous catalysts has been studied. These catalysts were prepared in three different areas of the synthesis of coordination polymers and metal-organic frameworks, supported palladium nanoparticles on these polymers, and production of metal oxide nanoparticles. At first, metal organic frameworks of cobalt and manganese transition metals were synthesized through hydrothermal method. In order to prepare these frameworks, 1,4-benzenedicarboxylic acid (terephthalic acid) and 2-amino-1,4-benzenedicarboxylic acid ligands were utilized as spacer ligands. X-ray analysis indicated that the structure of polymers is composed of secondary building units (SBUs) of... 

In this thesis, ionic liquids and polymeric ionic liquids were investigated as solvent and support for immobilization of molybdenum and palladium catalysts. Three newly synthesized room temperature ionic liquids containing molybdate anion, [DMIm][MoO2(NCS)4], [RPy][MoO2(NCS)4] (R = butyl or decyl), and previously reported [BMIm][MoO2(NCS)4] were used as catalysts for the reduction of sulfoxides. For facilitating the recyclability of the catalysts, the ionic liquid solvents, [RMIm][PF6] and [RPy][PF6] (RMIm=1-n-alkyl-3-methylimidazolium, RPy= 1-n-alkylpyridinium), were applied to immobilize molybdenum catalysts. These catalysts showed high catalytic activity for sulfoxide reduction in this...