An efficient n-doped electron transport layer composed of 4, 7-diphenyl-1, 10-phenanthroline (BPhen) and dipotassium phthalate (PAK2) has been developed. By temperature-dependent admittance spectroscopy, the incorporation of PAK2 into BPhen is found to increase electron concentration in BPhen layer, resulting in raising the Fermi-level to ̃0.5 eV below its LUMO which further enhances the efficiency of electron injection from Al cathode. When this n-doped layer is adopted in OLED device, the green Alq3 device can achieve a current efficiency of 3.6 cd/A and a power efficiency of 2.1 lm/W at 20 mA/cm 2 and lower drive voltage of 5.3 V.
|Number of pages||4|
|Journal||Digest of Technical Papers - SID International Symposium|
|State||Published - 30 Oct 2008|
|Event||2008 SID International Symposium - Los Angeles, CA, United States|
Duration: 20 May 2008 → 21 May 2008