Research On Opticalcal Culation Of Organic Solar Cells Based On Transfer Matrix Method

In this paper, a theoretical model based on transfer matrix method and MATLAB computing software were employed to investigate and optimize the properties of organic solar cells of different structures, which include the following aspects:The effects of device structure, active layer thickness, carrier transport layer thickness and different electrodes on the optical properties of P3HT:PCBM polymer solar cells were studied. The results indicated that the device with inverted structure and225nm thick P3HT:PCBM had the optimal optical property, Jsc for15.5mA/cm2, efficiency for5.77%. The inverted devices with Ag and Al electrode showed similar JSc, while the ones with Au electrode had inferior Jsc. The electron transport layer TiO2can be used as an optical spacer to change the optical electric field distribution inside device to enhance the light absorption in normal devices.The performance of the rubrene/C7o planar heterojunction solar cell was investigated, especially the effects of layer thickness of the rubrene and C70on the total absorbed photons density in the active layer. It was revealed that the optical interference played an important role in the performance of the device and the optimal device performance was achieved when the thicknesses of the rubrene and C70were set as33nm and28nm, respectively. The same devices were fabricated and tested and the results were consistent with the theoretical calculation.The short-circuit current density for tandem cells composed of different combinations of PCPDTBT, P3HT, PCeoBM and PC70BM were calculated. The results showed that PC70BM had superior optical and electrical properties than PC60BM. Optimal tandem cell with a high bandgap P3HT:PC7oBM bottom cell and a low bandgap PCPDTBT:PC7oBM top cell achieved maximum efficiency for10.9%under the suppose that the internal quantum efficiency equals1.