| 초록 |
Two blue fluorescent materials, m-PO-ABN and p-PO-ABN, are newly synthesized by controlling theconjugation length based on different linkages of the meta or para position between the phenanthro[9,10-d]oxazole (PO) moiety and anthracene substituted with a cyano group. The two materials emit deep-bluelight with a high photoluminescence quantum yield (PLQY) in solution state. Non-doped devices fabricatedusing m-PO-ABN and p-PO-ABN show the EL peaks at 448 and 460 nm corresponding to the CommissionInternationale de L’Eclairage (CIE) coordinates of (0.148, 0.099) and (0.150, 0.164), respectively. The externalquantum efficiency (EQE) values of the devices are 5.9% and 5.3% for m-PO-ABN and p-PO-ABN,respectively. Transient EL measurements and optical calculation results reveal that both materials exhibitgood charge balance and triplet–triplet annihilation in the devices, which may originate from enhancedbipolar characteristics due to the insertion of PO and cyano moieties. |
