| Recently, the organic conductive polymers have developed rapidly. One side they have flexibility and workability same as the traditional polymers, on the other hand they appear as close to the characteristics of inorganic semiconductor or conductive metal because of the conjugated structure. The two features are conducive to their application in the field of solar cells, offer an extremely favorable condition to reduce the cost of organic solar cells and make them have Commercial value and potential.This paper commences the study mainly around application of the new conductive polymer materials in the organic polymer solar cells. We chose two different polymer materials PPDIC and PFTST. PPDIC is the perylene imide-based n-type semiconductor polymer. Such polymers have more coordination of the absorption bands of the donor and the acceptor to as large as possible to improve the scope of the use of sunlight, and are conducive to Acceptor energy level matching. PFTST is the polyfluorene polymer derivatives with both functional groups of donor and acceptor. Its light stability and thermal stability are good.We have chosen donor or acceptor materials according to the material properties and the known parameters to prepare solar cell devices.About the receptor material PPDIC, we have found the P3HT/PPDIC polymer solar cells have a broad absorption spectrum, a higher exciton dissociation efficiency and large open circuit voltages through the absorption, emission spectra and device characterization experimental study. The largest open circuit voltage is 0.86V, and the best doping ratio of solar cells is P3HT:PPDIC= 1:1. Although the short-circuit current of the solar cells is small but we have improved the device performance by annealing. We have found the optimal annealing temperature is 140℃. At this temperature, the short circuit current is 1.8 times of that without annealing, the fill factor increased from 18.7% to 53.7%, and the device PCE increased by 4 times. By AFM, GIXRD characterization analysis, we believe that major improvements in the appropriate annealing temperature within the film interface exciton dissociation and carrier transport channel, so that device performance is greatly improved.About the polymer material PFTST with both kinds of functional groups of D and A, we separately studied the two systems that PFTST as donor and acceptor materials.When PFTST was the donor, the PFTST/PCBM polymer solar cells had larger open circuit voltages, the Voc of basic device was 0.77V, the Jsc is about several 10-1 (mA/cm2)s. We found the best doping ratio of solar cells is PFTST:PCBM= 1:2 through the device experiment and characterizations of film materials. We improved the device performance by annealing and adding a mixed solvent. When the annealing temperature was 120℃, the Voc reached 0.86 V, the short-circuit current density was 0.31 mA/cm2, the photoelectric conversion efficiency increased more than twice comparing that without annealing. We also greatly improved the device performance adding 1,8-octanedithiol as the solvent mixture.The photoelectric conversion efficiency was up to 0.136%.With the adding of mixed solvent, arrangement of two kinds of molecular is more conducive to the transmission of carriers, while maintaining good interfaces for exciton dissociation. So the short-circuit current and PCE of the device was greatly improvedWhen PFTST was the acceptor the performance of P3HT/PFTST polymer solar cells was not good as that of PFTST/PCBM polymer solar cells, while they still had photovoltaic properties. The best doping ratio of solar cells was PFTST:PCBM= 2:1. Also we improved the device performance by annealing. The PCE at the optimum annealing temperature (120℃) was about 7 times of that without annealing.Compared with the mature D or A polymer materials, the performance of the new materials we have selected is still weaker. We hope get better results by interface modification, the active material doping, adding optical buffer layer and so on.
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