Synthesis,Characterization And Application Of Polyaniline For Solar Cell

The discovery of the conducting polymers supplies a new kind of photo voltage materials for solar cell which has a good stability in air and it can be prepared easily with rich sources and very low cost. In addition, the conducting polymers have good flexibility and make the solar cell prepared by those materials flexible. Their advantages make it possible to produce low-cost solar cells. Good electrical conductivity and absorption within UV-visible and near infrared spectral region of polyaniline are excellent. Because its prices are very low the use of polyaniline material can be used as thin film light active material in solar cell and became a new hot.In this paper, we synthesized polyaniline as light activity materials of the thin film solar cell by the emulsion polymerization method and Chemical Oxidation method. We used dodecylbenzene sulfonic acid (DBSA), hydrochloric acid (HCl), sulfuric acid (H2SO4) as doping agent, ammonium persulfate ((NH4) 2S2O8) as oxidant to prepare PANI-DBSA, PANI-HCl, and PANI-H2SO4 compound respectively. We chose the PANI-DBSA to mix with ZnO powder to form a heterogeneous film on ITO glass by Spin-Coating as the optically active layer of solar cells. An Al electrode was manufactured by vacuum evaporation to form the solar cell devices. Transmission electron microscope (TEM) was used to observe the grain size and shapes; GM-Ⅱautomatic multifunctional resist instrument was used to test the conductivity of the composite material. The dissolution of PANI-DBSA in toluene solubility were tested and absorption properties of polyaniline and PANI-DBSA:ZnO light activity thin film in solar cell devices are tested by UV-Vis spectroscopy in 300～900nm and the optical-electro properties of the device are tested byⅠ-Ⅳtest system.TEM images showed that the shape of PANI-DBSA is spherical particles, the shape of PANI-HCl and PANI-H2SO4 are nano-tubes. The results of conductivity tests showed maximum conductivities of PANI-HCl, PANI-DBSA, PANI-H2SO4 were respectively 362S/m,150.4S/m, 162S/m. Solubility tests showed that PANI-DBSA can be soluble in toluene and the solubility was 3.76%.UV-Vis spectra showed that PANI-DBSA in UV-visible spectrum areas exist three different absorption peaks, they are at 340～360nm (peak I),420～440nm (peakⅡ), and 740～760nm (peakⅢ); PANI-HCl and PANI-H2SO4 in the UV-visible spectrum has two absorption bands, one of the absorption bands (bandsⅠ) in the red and near infrared band (350～470nm), the other absorption band (bandⅡ) in the violet and ultraviolet band (650～800nm); PANI-DBSA:ZnO light activity thin film in UV-visible spectrum areas exist four different peaks, they are at 340～360nm,380～400nm,420～460nm and 740～780nm. The photovoltaic test image showed that the deviceⅠ-Ⅴcurve is the Schottky diodeⅠ-Ⅴcurve.