Improving the Performance of Polyfluorene-Based Organic Light-Emitting Diodes via End-capping (pages 565–570)
T. Miteva, A. Meisel, W. Knoll, H. G. Nothofer, U. Scherf, D. C. Müller, K. Meerholz, A. Yasuda and D. Neher
Article first published online: 18 APR 2001 | DOI: 10.1002/1521-4095(200104)13:8<565::AID-ADMA565>3.0.CO;2-W
Efficient deep-blue electroluminescence(EL) is obtained via end-capping polyfluorene (PF) homopolymers with hole-transporting moieties (HTMs). Strong evidence that the observed improvement in device performance is related to the end-capper moieties comes from the comparison of two different end-cappers. The HTM does not disturb the liquid-crystal properties of the PF polymer. Using doped polyimide alignment layers, polarized light-emitting diodes (LEDs) with a polarization ratio in excess of twenty at an efficiency of 0.25 cd/A could be realized.