Design,Synthesis And Property Research Of Electron Acceptors Based On Perylene Imide And Metal Complex

In recent years,organic solar cells have attracted widespread attention because of their advantages like diversified species,low cost,and producible for flexible devices.One of the limitation in commercialization of organic solar cells is the lack of high performance materials for active layers.Organic semiconductors with triplet show longer life time of excited state than that of singlet ones,which allows them to transport excition for longer time and longer distance.Perylene imides are excellent acceptors with high light and chemical stability and strong visible absorption.In this study,metal complexes were introduced to the conjugated cores of perylene imides to enhance the excited state lifetime.There are three parts as following:1.Design,synthesis,and characterization of perylene diimide and ferrocene acceptor molecules.Three-dimensional diperylene diimide molecules 6 and 7 were synthesized by Suzuki coupling reaction.They have strong and wide absorption between 300-600 nm and low-lying LUMO levels(-3.84 eV and-3.66 eV).With the introduction of ferrocene,these molecules show the property of triplet,and the lifetime of excited state are prolonged effectively.The excited state lifetime of 6 reaches 0.81 ?s,and 7 reaches 0.46 ?s.These compounds have obtained about 1%of PCE in the organic solar cell devices,which proved their potential in organic photovoltaic.2.Design,synthesis and characterization of acceptor molecules based on modified perylene monoimide and metal complexes.The perylene monoimide ligand which contains structure of hydroxyquinoline were synthesized by a Suzuki-Heck tandem reaction.The ligand reacted with iron and nickel to obtain three-dimensional complex receptor molecules 18 and 19.They have low-lying LUMO levels(-3.70 eV and-3.69 eV),wide absorption range(300-850 nm),and strong near-infrared absorption.Their excited state lifetime has reached 0.19 ?s and 0.28 ?s.These compounds have obtained about 1%of PCE in the organic solar cell devices,which also provided some protential materials applied in organic photovoltaic.3.Design,synthesis and characterization of perylene monoimides near infrared dyes.An important factor in the design of efficient receptors is adjusting the absorption wavelength to the near infrared region.In this study,two perylene monoimides NIR absorption dyes 20 and 21 were synthesized by introducing push-pull electron systems with absorption ranges of 600-850 nm.With the help of theoretical calculation,the reason of absorption redshift is elucidated.The oxygen anion on the aromatic ring converted into quinone structure,which lead a strong electron-absorbing capacity and enhances the push-pull electron system of the whole molecular structure.It provides an idea for wavelength adjustment of electron acceptor design.