| Recently, more attention is focused on experimental research on quantum dots solar cells which is called the next generation solar cells. Narrow gap semiconductor quantum dots is prepared easily and has a low cost. Quantum dots used as sensitizer for solar cells has many advantages:(1) it can match the sunlight absorption spectra by controlling the size of quantum dot energy level structure of regulation, (2) Electric Dipole Moment of quantum dots makes it have a rapid charge separation, (3) Quantum dots has a high photoelectric conversion efficiency because it can generate multiple electrons when it absorbed a photon. But the photoelectric conversion efficiency of quantum dots sensitized TiO2 porous film has been low. The most likely reason for this is that the solar cells would have light degradation and instability of light because the photo-induced electron has a recombination at quantum dot surface of the recombination.Aromatic substituted imidazole is one of excellent organic functional materials with with high thermal stability and good electronic transmission performance. it can be used as electron donor(D) linked with [60]fullerene which has strong electron accepting ability o form a molecular D-A system. C60-Donor system can produce light-induced charge separation state, which plays an important role in the photoelectric conversion of organic solar cells.In this paper, we designed and synthesized two [60]fullerene-Donor system 7 and 8 from the mother material of benzil and 9-Ethyl-9H-carbazole, through Nitrationa reaction, Acetylation reaction, Radziszewki and Prato reaction. Two aromatic substituted imidazole compounds including 4-(4,5-bis(3-nitrophenyl)-1H-imidazole-2-yl)-3,6-biacetyl-9-ethyl-carbazole(5) and 4-(1-benzyl-4,5-bis(3-nitrophenyl)-imidazol-2-yl)3,6-biacetyl-9-ethyl-carbazole(6) have been synthesized at the first time. The processing condition of cycloaddition reaction was optimized and its reaction mechanism was also studied. The intermediates and the target products have been characterized and confirmed by IR, 1H-NMR, 13C-NMR, MS. The electrochemical properties of the compounds have been sdudied by ultraviolet-visible absorption, fluorescence spectra and cyclic voltammetry. The results show that compound 5 and 6 have the same spectra for their similar structure. But compound 6 has a blue-shift in the absorption and emission in the ultraviolet spectra because it was introduced the benzyl group. And the same influence can be also found in the fluorescence spectra. The fluorescence emission peak of compound 5 (494 nm) has a 70 nm blue-shift compared to compound 6 (424 nm) in the identical solvent. There is two new absorptions at 432 nm and 700 nm of compounds 7 and 8 in the ultraviolet-visible spectra. These are the characteristic peaks of Fulleropyrrolidine Derivates. The reduction potential of compound 7 and 8 shifts to the negative direction compared to C60 in cyclic voltammetry, it illuminates that the Fulleropyrrolidine Derivatives with aromatic substituted imidazoles used as electron acceptor have better performance.We assembled three sensitized solar cells and four QD-based solar cells by depositing photoactive QDs directly onto thin TiO2 films to demonstrate a new type of quantum-dot-sensitized solar cell. When illuminated with AM1.5 light, the quantum-dot-sensitized solar cells exhibited larger short-circuit current densities and open-circuit, had a higher quantum efficiencies comparable to those dye-sensitized solar cells made using Fulleropyrrolidine Derivatives and CdSe QDs. That's probably single QDs particles were vulnerable to impurities and lattice defects and there were a large number of non-radiative recombination centers. By preparing the protective shell C60 on core CdSe QDs, it can remove surface defects of QDs and increase the physical and optical stability.It is not a simple additive effect arising from individual components, but reflects the synergy arising from the excited interaction between CdSe and C60.
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