Organic Solar Cell Materials And Devices

Making low cost high efficient solar cells from materials of low price have been emphasized in an the research field of solar cells. At present, the application of solar cells used on the ground is limited mainly because of the complexity of producing processes and the high cost of single crystal and macrocrystal silicon. The discovery of electric conducting polymers supplies new materials and makes it possible to research and develop photovoltaic cells of low cost. In this dissertation, we choose polyaniline as a research material, which has good optical electric and photovoltaic characters, its synthesis, doping, composites, optical-electrical and solar cells are studied. Some promising results are obtained.Firstly, electrical conducting mechanism of polyaniline is reviewed. The paper describes the synthesis of polyaniline by chemical oxidizing process, and studies the effects of different reaction conditions on the polyaniline properties, including different oxidant, different amounts of oxidant, reaction temperature, reaction time, kinds and concentration of acid. The optimum polymerization condition is obtained, referring to the factors of the low cost, yield, conductivity.Secondly, polyaniline is doped with different kinds and thickness of acid again. The structure and properties are characterized by IR spectra, UV-Vis spectra and conductivity. Some result have been acquired, which best term of higher conductivity rate and the construction and optical-electrical of polyaniline are relative with kinds and thickness of acid again.Thirdly, the polyaniline/poly(vinyl alcohol) conductive composites are synthesized by "In-stiu" polymerization. The structure,photoelectric and stability of the composites are characterized by using conductivity, IR spectra, UV-Vis spectra, fluorescent and TGA. The result shows that this composite has very high conductivity whose value is up to 4.55S/cm. Its structure in IR spectra is the same with that electric polyaniline; its absorption band in Uv-vis spectra became wider and shifted to the blue region. Fluorescent spectra shows the irradiance efficiency improves. Better environmental stability is indicated from TGA and conductivity in the air in long time.Finally, the photovoltaic characteristics of polyaniline are also investigated. The voltage-current curve, the relationship of light intensity and open voltage and short current and stability of polyaniline heterojunction solar cells are tested, the various effect factors on polyaniline heterojunction are discussed as well, and some result that are never reported in published paper have been acquired.