The Cathode Interface Modification Research In Polymer Solar Cells With Alcohol Soluble Conjugated Polymer

Polymer solar cells attracted widespread attention due to its own practical characteristics and processing advantages. It is one of the most potential solar cells that to achieve large-scale commercial applications. With the development of the new materials synthesis and the device physics of the polymer solar cells, the efficiency and the stability of the device have made great progress in recent years. In spite of this, it has not reached the standard of business applications, and the polymer solar cells already need to be further studied. Suitable modifications interface layer is important to the performance and the stability of the device, so the study of the device interface modification layer is also an important research focus in recent years, especially the cathode interface modification.This thesis is mainly focus on the study of the polymer solar cells cathode interface modification layer. On the base of explaining the background and the development history of the polymer solar cells, the necessity of its study is analysised. On the base of this, the thesis also describes the research status of the electrode interface layer. To better understand the polymer solar cell device, its complete preparation process and testing process are been expounded, and its main performance parameters are also been analyzed.Because the alcohol soluble conjugated polymer as the polymer solar cell device cathode interface layer has significant practical advantages, the alcohol-soluble conjugated polymer PBN and PBNBr have been designed and synthesized. It is found that they are all having preferable luminousness, in addition they can reduce the work function and improve topography of the interface of ITO, after the light transmittance, the impact on the roughness and the work function of ITO were texted.On this basis, by the polymer photovoltaic devices characterization, PBN and PBNBr as the inverted device cathode interface modification layer were characterized firstly. It is found that they are all having good electrical and optical properties. As the P3HT:PC61BM prepared for the active layer, the good performance of the inverted devices photoelectric conversion efficiency 4.24% and 4.53% have been made. Zn O is commonly used in the inverted devices cathode interface modification layer due to its good optical properties and electrical properties, but there are many materials after modification its interface can improve the efficiency of the device, therefore this paper also tried to use PBN and PBNBr further modifying ZnO interface, and found that after PBN and PBNBr modified ZnO, it can significantly improve the device performance.Because the PBN has processing advantages, this thesis try to prepare the device using P3HT: PC61 BM as the active layer, PBN is to replace the traditional upright devices live wave metal(Ca, Mg, etc.) as the cathode interface to prepare the device. It found that PBN as a traditional upright cathode modification layer device can observably improve the efficiency of the device. It indicates that PBN can be used as the traditional upright device cathode interface modification layer.Tandem polymer solar cell structure is an effective way to improve the efficiency of the device. On the above basis, this paper also attempts to use PBN in the tandem polymer solar cells intermediate link layer. By optimizing each conditions, The structure of MoO3/Ag/PBN intermediate link layer that has good optical and electrical properties is prepared. Using P3HT: PC61 BM as upper and lower subcells of the active layer, and MoO3/Ag/PBN as intermediate link layer prepared a tandem device, which have superimposed open-circuit voltage(1.19 V), high fill factor(62.91%) and high photoelectric conversion efficiency that more than 3%. We believe that if using the high performance materials which has complementary absorption spectra, the more excellent high efficiency tandem devices will be prepared.