| As the energy crisis has been a global problem, the exploitation and utilization of the solar power become an effective way to solve this problem. An important components of which is the development of solar cells. Single crystalline silicon solar cells have high photoelectric conversion efficiency, but because of the preparation technology is complex and dosage, the cost is very high. As the advantage of its wide range of absorption of the solar spectrum, controllable size can be large-scale preparation and potential Multiple Exciton Generation effect, the quantum dot solar cells is possible to significantly reduce the solar cells production costs.Quantum dot solar cells have great potential for development, especially the PbSe quantum dots for narrow forbidden bandgap, the big Bohr radius to its light absorption range can be extended to the near infrared and visible light has attracted widespread attention. As the Klimov team reported that when PbSe quantum dots using high energy ultraviolet ray bombardment, each absorbing photons can produce7excitons. However there are so many factors that affect the solar cell performance in practical assembly process, the research about PbSe quantum dots used as sensitizer in solar cells is not much, so if the Multiple Exciton Generation effect is to be applied to the quantum dot solar cells,there must be a comprehensive exploration in the process of assembly.Therefore, in this paper, for the purpose to explore the influence factors in the process of assembly in the PbSe quantum dot solar cells, the synthesis of PbSe quantum dots and the actual problems encountered in the process of assembly were studied in some impact on cells performance. The research content in detail are as follows:(1)The PbSe quantum dots were prepared by high temperature injection method, the synthesis method was improved. The effection on morphology and the size of the QDS from reaction temperature, reaction time and the solvent additive effect are reported. The most appropriate reaction conditions were determined. The phase and crystallization of the quantum dots were characterized by powder X-ray diffraction (XRD).The size and morphology were observed using Transmission electron microscope (TEM). The test indicates that the PbSe quantum dots had different shapes such as the diamond, hexagon, octagon and hexagon star. The PbSe nanoparticles with different sizes and shapes were analyzed, and the possible growth mechanism was proposed.(2) The sol titanium dioxide nanoparticles were prepared by sol-gel method. The sol and the P25titanium dioxide nanoparticles were respectively prepared into anodic solar films which were characterized by scanning electron microscope (SEM) and sensitized by PbSe quantum dots. The conditions for assembly of the assembled quantum dot solar cells were explored.(3)The effection of the anodic film, different size and morphology of PbSe sensitizer and different sensitizing time were studied respectively, ultimately the best performance we got as follows:under AM1.5simulated sunlight irradiation, the short circuit current is2.5mA/cm2, the open circuit voltage is0.48V, fill factor is0.39, the energy conversion efficiency is0.47%of the quantum dot solar cells. |
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