| 초록 |
Our hole injection material, namely, 10,10’-bis(4-tert-butylphenyl)-N7,N7’-di(naphthalen-1-yl)-N7,N7’-diphenyl-10H,10’H-3,3’-biphenoxazine-7,7’-diamine (1-PNA-BPBPOX) were adapted to white OLED devices for solution process. By incorporating adjacent blue and orange emitting layers in a multi-layer structure, highly efficient white emission has been attained. The device was fabricated with hybrid configuration structure. White devices were fabricated using a multilayer emission structure consisting of a single host layer. The red phosphorescent, tris(2-phenyl-1-quinoline)iridium(III) [Ir(phq)3], and the blue phosphorescent, iridium(III)bis[(4,6-di-fluorophenyl)-pyridinato-N,C2]picolinate (FIrpic), are doped into separate layers of N,N-dicarbazolyl-3,5-benzene (mCP) host. The FIrpic and Ir(phq)3 guest molecules are directly excited by direct recombination on these molecules. In the device, the maximum value of UV–visible absorption (UV-vis) of hole injection layer PNA-BPBPOX is 366 nm in solution state and 370 nm in film state, not showing absorption of visible light. When the device with BPBPOX was compared to the device with PEDOT:PSS a commercialized solution HIL material, luminance efficiency was 6.37 cd/A for PNA-BPBPOX and 0.66 cd/A for PEDOT:PSS for the optimized white device structure, showing 10 times as high efficiency. |
