Design、synthesis And Properties Of Organic Photovoltaic Materials Based On Quinoxaline And Carbazole Derivatives

Organic photovoltaics(OPVs), recently have attracted widespread interest in terms of its low cost,easy of processing, favorable performance and environmentally friendly, compared to conventional cells. As members of OPVs, dye-sensitized solar cell(DSSCs) and polymeric solar cells(PSCs) are considered as the most promising cells. In order to improving the performance of the cell further more,obtain high power conversion efficiency,researchers need to synthetise novel materials and comprehend the relationship between the structures and the performances.In last years, polymers and dye sensitizers based on quinoxaline,carbazole and porphyrin have attracted great attention gradually. Quinoxalines are strong electron-accepting materials due to their high electron affinity originated from the two symmetric unsaturated nitrogen atoms. Carbazole, with big π- conjugated system and outstanding transmission carrier capability,has excellent photovoltaic performance and is suitable to be used as hole transport materials.porphyrin which has π-conjugated planar structure can transfer electron effectively.Herein,we design and synthetise dye sensitizers and polymers based on groups mentioned,apply them to OPVs. Following is our aspects of work:Design and senthetise two polymers based on porphyrin(P1, P2),both polymers exhibit good solubility and thermal stability(5% weight loss temperature above 400 oC). The absorption spectrum is broaded to 800 nm in terms of introduction of perylene group.The optical band gap of the polymers are 1.92 eV and 1.56 eV.Design and senthetise a series of dye sensitizers based on quinoxaline(D1-D3). Rigid the π-linker with fastening atoms C and S, which makes the molecualr unrotatable. Both sensitizers exhibit good solubility, broad absorption(400-700 nm).A series of dye sensitizers based on carbazole were designed and senthetised. Discuss the influence of group replacement to the performance of cells and research the relationship of different molecules combination and the performance of cells by changing the position of carbazole derivatives and diazosulfide. Excellent solubility is exhibited with broad absorption(400-650 nm).