الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
Our aim in this thesis was to prepare PANI in different forms in the nano-scale by an environmental friendly method by one from the green chemistry approaches which is the solid state reactions. The presented work aims to preparation of some polyaniline(PANI)/metal nano-composites. PANI nano-particlesand Ag@PANI core@shel lnano-composites were prepared using solid state polymerization method in the presence of different concentration of ammonium peroxydisulfate (APS)in the case of PANI nano-particles synthesis and AgNO3 for the preparation of PANI@Ag core@shell. The vibrational structure and electronic transitions were studied using FTIR and UV-Vis spectroscopic techniques. FTIR data revealed that the formation of PANI nano-particles and Ag@PANI core@shell nano-composites are in doped state and emeraldine salt (ES) form. UV-Vis data of PANI nano-particles and Ag@PANI core@shell nano-composites at different amount were investigated. It was found that the electronic absorption bands of PANI nano-particles showed no detectable shift in wavelength with increasing amount of APS and new band appeared. The electronic absorption bands of Ag@PANI core@shell nano-composites showed that some bands have no detectable shift and others shifted. PANI nano-particles and Ag@PANI core@shell nano-composites were formed in emeraldine salt form. The optical band gap of PANI nano-particles and Ag@PANI nano-composites with different concentration were calculated from the UV-vis spectra. It was found that the optical bandgap was shifted to low and high values as the particle size increased and decreased for PANI nano-particles and Ag@PANI core@shell nano-composites respectively. This behavior could be attributed to the quantum confinement. The effect of amount of silver nitrate on the crystallinity index and particle size of Ag@PANI core@shell were studied using X-Ray Diffraction (XRD), Transmission Electron Microscope (TEM) and Scanning Electron Microscope(SEM). It was found that the particle size of PANI nano-particles increased with increasing concentration of APS. The particle size of Ag@PANI core@shell decreased with increasing concentration of AgNO3.XRD data revealed that crystallinity index of Ag@PANI core@shell increased with increasing concentration of AgNO3. THE quantum mechanical calculations have been utilized using the density function theory (DFT) byB3LYP method on the basis set 6-31g(d,p) to calculate the single point energy of Polyaniline emeraldine nitrate salt (PANI-nitrate). Polyaniline emeraldine sulphate (PANISulphate) was also calculated on the same level. At the end the Ag@PANI-nitrate core-shell was calculated on the same level of calculations. For the previously named structures,the total dipole moment vector of every molecule was also calculated in addition to the energy band gap between the highest occupied molecular orbital (HOMO) and the lowest occupied molecular orbital (LUMO) and the distribution of the Electrostatic potential. More investigations for the studied molecules have been done in the presence of water molecules.