Reseach On The Modified Layer In Organic Small Molucile Solar Cells

Economic development makes energy demand and the use of fossil fuels rising rapidly, which also led to the greenhouse effect, caused great damage to the ecological environment. It is imperative to search for new clean energy. As a new type of clean energy, solar energy has been received extensive attention, because of its inexhaustible less affected by the geographical environment. Compared with traditional silicon solar cells, organic solar cells have many advantages. It can be produced through simple process, also can make the flexible components with cheap materials. These advantages make organic solar cells have a very bright prospects for development. At present, the photoelectric conversion efficiency of organic solar is still relatively low. The structure of organic solar cell optimization is an important way to improve the performance of organic solar cells. As the newest field of organic solar cell structure optimization, The modified layer can effectively improve surface of the absorption layer in organic solar cells and the This paper mainly studied the following aspects:1. Research on small molecule organic solar cells with Cu I as modified layer: We use CuI as modified layer, import the TAPC: C70 system organic solar cells and DIBSQ: C70 system organic solar cells respectively. Then we test the performance change of the devices after the import of modification layer. We also change the Cu I modified layer thickness to explore the best the thickness of the modified layer. The result show that, for TAPC: C70 system, the modified layer thickness of 5nm can maximum increase the performance of the device, the photoelectric conversion efficiency of the device is increased from 4.76% to 5.76%, increased by 1.00%, lifting ratio reached 21.2%; for DIBSQ: C70 system, the modified layer thickness of 5nm can maximum increase the performance of the device. The photoelectric conversion efficiency of the device is increased from 4.40% to 5.00%, rising to 0.60%, enhance the ratio of 13.6%.2. Research on small molecule organic solar cells with BP2 T as modified layer. We use BP2 T as modified layer material, import the DTDCTB: C70 system organic solar cells. Then we test the performance change of the devices after the import of modification layer. We also change the thickness of BP2 T modification layer to explore the best the thickness of the modified layer. The result show that the modified layer thickness of 10 nm can maximum increase the performance of the device, the photoelectric conversion efficiency of the device is increased from 3.56% to 4.00%, increased by 0.44%, increase the ratio reached 12.36%.3. We test the changes of the absorption spectra and surface morphology after the import of modified layer to explore the mechanism of modification layer. The results show that the import of modified layer did not affect absorption spectra of the device But it changes the surface morphology of the device, improve the surface roughness of absorption layer modification, that makes the exciton number and the probability of exciton separation increased. So the photocurrent of solar cell increased that makes the organic solar cells have better performance. In addition, we give a theory explanation of the phenomenon that the light current rise become smaller with thick modified layer.This article research has a certain reference significance to further enrich the theory of organic solar cells and promote the industrialization process of organic solar cells.