Phosphorescent OLEDs assembled using Os(II) phosphors and a bipolar host material consisting of both carbazole and dibenzophosphole oxide

Content Provider	Semantic Scholar
Author	Lin, Cheng-Huei Hsu, Che-Wei Liao, Jia-Ling Cheng, Yi-Ming Lin, Tsung-Yi Chung, Min-Wen Chou, P. Lee, Gene-Hsiang Chang, Chih-Hao Shih, Chin-Yao Ho, Chi-Lung
Copyright Year	2012
Abstract	We report on the synthesis of a new series of Os(II) complexes (1–3) functionalized with 2-pyridyl (or 2-isoquinolyl) pyrazole chelates, together with a new diphosphine, 1,2-bis(phospholano)benzene chelate (pp2b). The resulting Os(II) complexes are fully characterized and their structural versus spectroscopic properties have been comprehended by absorption/emission together with computational approaches. The inherent electron richness, restricted rotational barrier and good steric hindrance of pp2b lead to the production of both orange and red phosphorescence with high quantum efficiency. For exploring these Os(II) based OLEDs, we also synthesized a bipolar material 5-[4-(carbazo-9-yl)phenyl] dibenzophosphole-5-oxide (CzPhO), possessing both carbazole donor and dibenzophosphole oxide acceptor. Successful fabrication of OLEDs using complexes 1 and 3 as the dopant and either 4,4′-N,N′-dicarbazolebiphenyl (CBP) or CzPhO as host is reported. For comparison, the CBP and CzPhO devices with 1 as the emitter showed peak efficiencies EQE of 10.9%, ηL of 21.7 cd A−1, and ηp of 11.9 lm W−1, and EQE of 14.3%, ηL of 34.8 cd A−1, and ηp of 45.2 lm W−1, respectively.
Starting Page	10684
Ending Page	10694
Page Count	11
File Format	PDF HTM / HTML
DOI	10.1039/C2JM16674G
Volume Number	22
Alternate Webpage(s)	http://www.rsc.org/suppdata/jm/c2/c2jm16674g/c2jm16674g.pdf
Alternate Webpage(s)	https://doi.org/10.1039/C2JM16674G
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article