초록 |
Spirobifluorene-based electroluminescene (EL) polymers, poly(9,9'-spirobifluorenyl-2,7-vinylene) (spiro-PFV) and poly[(9,9'-spirobifluorenyl-2,7-vinylene)-co-(9,9-di-n-octylfluorenyl-2,7-vinylene)] (spiro-PFV-co-PFV) and poly(3',6'-bis(3,7-dimethyloctyloxy)-9,9'-spirobifluorenyl-2,7-vivylene) ((RO)2-spiro-PFV), have been synthesized by Gilch polymerization method. Spiro-PFV was only soluble in toluene, but spiro-PFV-co-PFV and (RO)2-spiro-PFV were completely soluble in common organic solvents, so easily spin-coated onto ITO-coated glass substrates. The organic light-emitting diode (OLED) based on the structure of ITO/PEDOT:PSS (30nm)/(RO)2-spiro-PFV (100nm)/Alq3 (20nm)/LiF (0.5nm)/Al (100nm) showed good device performance. The emission maximum of (RO)2-spiro-PFV was observed at 469nm. Maximum brightness and luminescence efficiency were obtained to 4060 cd/m2 at 14V and 1.18 cd/A at 9V, respectively. The color coordinate in CIE chromaticity was (0.26, 0.40). The full width at half maximum (FWHM) of (RO)2-spiro-PFV was more narrower than PFV in EL spetrum, and PFV was observed in increasing of long wavelength emission in 500-600nm by increasing of voltage but (RO)2-spiro-PFV did not showed long wavelength emission. |