مكان الجامعة: البصرة

الصفحات الاولى:

المستخلص: The present thesis Conducts polymer (polyaniline) doped with Dodycyl Benzene Sulfonic Acid (DBSA) was prepared by chemical polymerization and with the help of ammonium persulphat (NH4)2S2O8 as oxidizing agent.Multi well carbon tubes MWNTs are ultrasonically treated with strong acide using a 3 : 1 mixture of concentrated H2SO4 and HNO3, producing carboxylic groups c - MWNTs .Nanocomposite conducting polymers PANIDBSA/ MWCNTs was prepared with adding different weight ratios (0%,1%,2%,3%,5%)(MWNCTs to PANI - DBSA). Accordingly, films of these nanocomposite polymer were prepared by spin coating technique .To study the optical properties, these films were deposited on glass, and on interdigitated finger electrode for the - electrical properties.The chemical structure of the prepared polymers PANI - DBSA, c - MWNCT and PANI - DBSA/MWCNTs are characterized by the FTIR spectra .The results indicated an appearance of functional group of doping with DBSA and MWNCTs changed to c - MWNCTs.The structure of preparation films are characterized by X - RAD diffraction .The results show crystalline peaks partial crystallinity of the PANI - DBSA/MWNCTs. The grain size of polymer was calculated by Scherrer relation.Morphologies and diameters of the nanocomposite were studied by Atom ic Force Microscope(AFM) and Scanning Electron Microscope (SEM). The average diameters of nanocomposite change between (81 - 118) nm and the roughness increased with increasing of MWNCTs in nanocomposite. Ology and the thickness were measured by Scanning Electron Microscope (SEM).The result shows the polymer covered MWNCT.The optical properties of preparation film were studied from absorbance spectra at wave - lengths of (300 - 1100 nm). The analyses of optical measurement shows direct transition with energy gap decreasing increases MWNCTs about(3.4 - 1.9) eV. The reflection spectrum is analysed to find same optical constant like extension coefficient and refraction coefficient.The electric conductivity was measured and it was found that the thin films correlate with the ohmic behaviour at voltage under 10V.The electricalconductivity increases as the ratios of MWNCTs increases in PANIDBSA/ MWNCTs nanocomposite from(6.17x10 - 3 S/cm ) at 0wt% to (1.12x10 - 1 ????/cm ) at 5wt% .The effect of temperature on the electric conductivity of all ratios of thenanocompositesare also studied. The resultindicated the activationenergy decrease as MWNCTs increase from 0.15 at (0wt %) to 0.05 at (5wt %).In electronic applications of nanocomposite conducting polymers solar cell,two kinds of solar cells (ITO/TiO2/PANI - DBSA/MWCNTs/C/ITO ) and (ITO/TiO2/PANI - DBSA/MWCNTs/dye/C/ITO) were fabricated. The currentvoltage characteristics are measured at light source 100mw/cm2.The solar cell parameter like open circuit voltage VOC ,short circuit current JSC, shunt resistance RSh, series resistance RS, full factor FF, and efficiency η, are calculated. The efficiency of solar cell at different ratios of MWNCTs in PANI - DBSA/MWNCT were calculated. The result indicated that the efficiency increased as MWNCTs increase. The efficiency of solar cells also increases with adding dye.