초록 |
In this study, we fabricated and characterized polymer light emitting diodes (PLEDs) by replacing PEDOT:PSS hole transporting layer with conjugated polyelectrolytes (CPEs). We synthesized CPEs which have identity polymer backbone and different terminal ionic groups. They were dissolved in methanol or deionized water and deposited on indium tin oxide (ITO) transparent electrode by spin-coating. Permanent dipole moment was formed between ITO and emitting layer by introducing CPEs. The dipole moment of CPEs was controlled by molecular arrangement, which was caused by different terminal ionic groups, and modified the work function of ITO electrode. To analysis the effects of different terminal ionic groups of CPEs, UPS, AFM, UV-vis spectrum and DFT calculation of CPE molecules were performed. In the optimized PLED, The device performances were enhanced, compared with PEDOT:PSS based device. |