Study In Photoanode Optimization Of Quantum Dot-Sensitized Solar Cells

Quantum dot-sensitized solar cells(QDSSC) has received wide attention from researchers because of its high theoretical energy conversion efficiency and low production costs. Actually, the efficiency of quantum dot sensitized solar cell is not high enough. There are many reasons for the fact, and not enough anode structure optimization is one of this. In this paper, the structure is from the anodic oxide film, the thickness of the quantum dots, several co-sensitizer quantum dots, enhancing the absorption of light and anode surface passivation treatment and other aspects of research in quantum dot sensitized solar battery light anode structure optimization. The main contents and results are as follows:1. Introduces the basic working principle of QDSSC, lists the structure of QDSSC including transparent conductive optical glass, transparent oxide semiconductor quantum dot sensitizing agent, electrolyte and electrodes in detail. Analysis the role of various components and its the use of principle in solar cell, and introduces the common material of all components and the arising possible problems of their using;2. Introduces the production methods and experimental procedures experiments of the preparation of a three-dimensional TiO2 on FTO glass and observe the surface morphology and TiO2 and draw three-dimensional TiO2 inverse opal by scanning electron microscope, then do a simple comparison with TiO2 nanowires. It is out to be that three-dimensional TiO2 inverse opal have a more regular hexagonal body than TiO2 nanotubes and nanowires. And ordered nanostructures regular hexagonal body and more aid in the separation and transfer of electrons and electron holes, which exist on the feasibility improve battery efficiency;3. Use reactive ion adsorption method(SILAR) to make CdS, ZnS and PbS quantum dots in TiO2 thin films, and make CdSe quantum dots at a constant temperature water. It is verified in experiments that CdS and CdSe quantum dots are highly complementary in the part of light absorbing. Use UV-visible spectrometer detected absorption spectrum to select the appropriate quantum dot layer thickness that is used to prepare the assembly of the battery, in order to obtain high efficiency solar cells possible. The results shows that the use of SILAR in quantum dots prepared process quantum dots preparation can strictly controlled thickness of the quantum dots, also more conducive to finding the right thickness of the quantum dots to improve efficiency of solar cells. Studies have shown that when you use SILAR prepared CdS quantum dots, etc, alcohol aqueous solution is more favorable than the aqueous solution in production of quantum dots, we can also learn that the best soak time in each solution is one minute when using SILAR method, and the best optimum number of cycles for each quantum dot layers is not the same;4. Use ZnS quantum dots as a role in the inner layer to enhance the absorption intensity of the quantum dot, use co-sensitizer and ZnS outer anode passivation optimizations to improve battery photoelectric conversion efficiency. Co-sensitizer can enhance the absorption range of quantum dots. Make suitable thickness ZnS between the quantum dots and TiO2 film by SILAR in CdS/CdSe co-sensitized solar cell and the efficiency of solar cell can reach 2.41 percent which is improved 61.7 percent more than the original. In addition, when using the three-dimensional TiO2 inverse opal structure, can CdS/CdSe co-sensitized solar cell efficiency reached 2.09%, on the basis of the original 1.49% improved 40.3%.There is also described that a stronger or more extensive range of light absorbance of quantum dots will not be able to obtain higher photoelectric conversion efficiency of the battery.