Research On Flexible Silicon Based Organic/Inorganic Hybrid Solar Cells

Solar photovoltaic cell is the core device that can convert solar radiation directly into electricity. The high cost, low efficiency and complex fabrication conditions of traditional silicon-based solar cells restrict its further development. Silicon-based organic-inorganic hybrid solar cells can integrate the low cost, easy operating properties of organic material and the excellent conductivity, high stability properties of silicon; and has obtained ideal efficiency in experiments. Additionally, developing flexible and ultrathin hybrid solar device, it will also has the unique advantages of small volume, light weight and wide applications; and fit the solar cell development directions that decreasing cost, increasing efficiency and enhancing portability. This article mainly studied the controllable fabrication of high quality, large-area ultrathin monocrystalline silicon wafer, and the structure design, material preparation and performance optimization of flexible ultrathin hybrid solar cells. The main research content is given as follows:(1) Researches on the original thickness silicon-based organic-inorganic hybrid solar cells are carried out. By carrying the work of conducting solution doping and cell structure changing, we studied the performance of DMSO-doping in PEDOT:PSS solution on the properties of film forming; we also studied the performance of fluorocarbon surfactants addition on the surface tension of PEDOT:PSS solution. We explored the effective measures of efficiency increase by characterizing and analyzing the performances of the devices, and the conversion efficiency of the silicon nanowires/PEDOT:PSS solar cell we fabricated has reached 9.31%.(2) We explored a controllable method of fabricating high quality, flexible, large-area ultrathin monocrystalline silicon wafers by solution etching. We also explored the impact factors on the thinning rate and surface roughness of silicon wafer by adjusting the parameters such as the concentration of the solution components, reduction temperature and thinning time. The studies we carried out can provide basis materials for the subsequent study of flexible ultrathin silicon-based organic-inorganic hybrid solar cells preparation and optimization.(3) We transplanted the original thickness of silicon-based organic-inorganic hybrid solar cell technology into ultrathin monocrystalline silicon wafer, and studied the structure optimization and efficiency increase measures of flexible ultrathin silicon-based hybrid solar cells. We fabricated three structures of flexible ultrathin silicon-based hybrid solar cells, they are planar silicon/PEDOT:PSS hybrid solar cells, back-pyramid silicon/PEDOT:PSS hybrid solar cells and back PEDOT:PSS hybrid solar cells, then analyzed their performances. The highest efficiency of back-pyramid silicon/PEDOT: PSS hybrid solar cell has reached 7.81%; while back PEDOT:PSS hybrid solar cell has theoretical advantages of high efficiency, and it will be very.promising when passivation technology is well applied on the bare silicon surface.