Department of Chemistry
Realization of highly efficient white polymer light-emitting devices via interfacial energy transfer from poly(N-vinylcarbazole)
We report highly efficient white polymer light-emitting devices (WPLEDs) using a newly synthesized, deep-blue emitting fluorene-co-dibenzothiophene-S,S-dioxide copolymer as host, doped with two narrow-bandgap iridium complexes. Despite the low-lying triplet energy levels of the host, phosphorescent quenching by the polyfluorene copolymer host was significantly suppressed with poly(N-vinylcarbazole) (PVK) as hole-injecting, anode buffer layer. The energy transfer process had been studied via transient photoluminescence spectra and confirmed that PVK layer is responsible for the efficient electrophosphorescence in the devices. As a result of balanced red-green-blue (RGB) emission from the host and the triplet emitters, white emission with Commission Internationale de L'Eclairage (CIE) coordinates of (0.278, 0.312) was achieved, with a peak luminous efficiency of 15.1 cd A-1 and a color rendering index (CRI) of 79-86. © 2009 Elsevier B.V. All rights reserved.
Phosphorescence quenching, Poly(N-vinylcarbazole), White polymer light-emitting devices
Source Publication Title
Li, Aiyuan, Yuanyuan Li, Wanzhu Cai, Guijiang Zhou, Zhao Chen, Hongbin Wu, Wai-Yeung Wong, Wei Yang, Junbiao Peng, and Yong Cao. "Realization of highly efficient white polymer light-emitting devices via interfacial energy transfer from poly(N-vinylcarbazole)." Organic Elecronics 11.4 (2010): 529-534.