Triplet energy transfer between a sacrificial PMP and blue TPF2 iridium dopants leading to enhancement of OLED device performance
발표자
()
초록
내용
In this study, we prepared phenylimidazole-based C^N-cyclometalated Ir(III) complexes (DMP, TPF2) and C^C-cyclometalated Ir(III) complex (PMP) and investigated the energy transfer process through intermolecular interactions between the two cyclometalated Ir(III) complexes. In films doped with 3% Ir(C^C)3 complex and 15% Ir(C^N)3 complex, the PMP effectively induced energy transfer to the DMP or TPF2. One case of mixing PMP with DMP, two types of luminescence were observed at 470 nm and 580 nm, 470 nm was the emission due to DMP, while the emission at 580 nm can be assigned as the intermolecular exciplex emission. The other case of mixing PMP with TPF2, the emission at 465 nm corresponding to the PMP emission region decreased for 4.5 ns while the emission at 530 nm corresponding to TPF2 increases. This emission can be assigned by energy transfer from PMP to TPF2. Finally, it was confirmed that the operation lifetime and efficiency of the device was improved by doping 3% of PMP in EML.