Synthesis And Photovoltaic Properties Of Organic Photovoltaic Materials Based On Porphyrin Dyes And Polymers

The main challenge that human survival and development faced is energy problem. As the fossil energy gradually reduces and the demand of energy increases in the world, the development of new energy has became a hot scientific research. Solar energy, as a kind of widely distributed, ample and eco-friendly energy, has caused the world’s research. Through decades of evolution, solar cells have been developed to the third type of organic solar cells(OSCs). But the time of this type of battery development is short, their photoelectric conversion efficiency(PCE) has not yet to reach the request of industrialization. So as to raise the photovoltaic performance of materials, broad the spectrum, enhance light absorption and regulate the molecular level of materials, we designed and synthesized six kinds of OSC materials. 1H-NMR, 13C-NHR and MALDI-TOF were used to characterize the structure of intermediates and the target product. We also use UV-vis spectra, PL spectra, Cyclic Voltammetry investigated photophysics, electrochemical, and photovoltaic performance of these material. The main contents are as follows:1. We designed and syntheszed three porphyrin dyes SF, BSF and NSF, respectively use triphenylamine and N, N-dimethyl-4-(acetylene)- aniline as donor, porphyrin derivatives as conjugated π bridge, ethynyl thiophene or ethynyl thiophthene as π spacers, carboxylic acid groups as anchor group. We conducted the optical physics, electrochemical and optical performance of those dys. Research shows that the absorption spectrum of both BSF and NSF which used ethynyl thiophthene as π spacer units have been broadened and red-shifted, meanwhile, there was a decrease of energy gaps between the HOMO and LUMO compared with SF. So that, BSF and NSF get higher photovoltaic performance. Dyes BSF and NSF exhibited PCE of 4.53% and 3.98% under AM 1.5 G irradiation(100 mW cm-2), respectively.2. We based on benzodithiophene(BDT) and diketopyrrolopyrrole(DPP) which had widely absorption in the visible area of as monomer, meanehile, porphyrin derivative which exhibited strong absorption in 400-500 nm range was introduced into the polymer, synthesis of a series of new type of random copolymer P1, P2, P3. And then, we investigate the performance of these three polymers. Experiments showed that the three copolymers exhibited good thermal stability and solubility. The introduction of porphyrin units in the copolymer P2, P3 could effectively broad the absorption spectrum; reduce the HOMO energy levels of polymer. Compared with binary alternating analogues P1, the two tercopolymers P2 and P3 exhibited the improved the PCE of 0.21% and 0.32%, respectively.