Three small molecules with the same arms and different cores of perylene diimide(PDI)or indaceno[2,1-b:6,5-b']dithiophene(IDT)were designed and synthesized as the acceptor materials for P3HT-based bulk-heterojunction(BHJ)solar cells.The impacts of the different cores on the optical absorption,electrochemical properties,electron mobility,film morphology,photoluminescene characteristics,and solar cell performance were thoroughly studied.The three compounds possess a broad absorption covering the wavelength range of 400–700 nm and relatively low lowest unoccupied molecular orbital(LUMO)energy levels of?3.86,?3.81 and?3.99 eV.The highest power conversion efficiency of 0.82%was achieved for the BHJ solar cells based on SM3 as the acceptor material,the compound with a PDI core.
LIU XinCAI PingCHEN DongChenCHEN JunWuSU ShiJianCAO Yong
A series of alcohol soluble amino-functionalized carbazole-based copolymers were synthesized via Suzuki coupling reaction. The pendent amino groups endow them high solubility in polar solvents, as well as efficient electron injection capability from high work-function metals. The relationships between the photophysical and electrochemical properties and the polymer backbone structure were systematically investigated. These alcohol-soluble carbazole-based copolymers were used as cathode interlayers between the high work-function metal A1 cathode and P-PPV emissive layer in polymer light-emitting diodes with device structure of ITO/PEDOT：PSS/P-PPV/interlayer/A1. The resulting devices exhibited improved performance due to the better electron injection/transporting ability of the designed copolymers from A1 cathode to the light-emitting layer.
