Highly efficient red light-emitting devices using copolymer containing charged iridium complex in the side chain

Lei Wang; Bin Du; Yong Cao; Jian Wang

doi:10.1117/12.768571

20 November 2007 Highly efficient red light-emitting devices using copolymer containing charged iridium complex in the side chain

Lei Wang, Bin Du, Yong Cao, Jian Wang

Author Affiliations +

Proceedings Volume 6828, Light-Emitting Diode Materials and Devices II; 68280I (2007) https://doi.org/10.1117/12.768571
Event: Photonics Asia 2007, 2007, Beijing, China

Abstract

Red emission was achieved in electroluminescent devices by using a novel charged Ir-copolymer. The electroluminescent device, with the configuration of ITO/PEDOT:PSS/Ir-copolymer/Au, exhibited the characteristics of light-emitting electrochemical cell (LEC), in which the redistribution of ions resulted in the ionic junction. The maximum external quantum efficiency (EQE) of 0.19 % and the maximum luminance of 352 cd/m² were obtained after the device was driven to the maximum luminance at 7V. When aluminum (Al) was used as cathode, the maximum EQE of 0.15 % and the maximum luminance of 340cd/m² were achieved, which were comparable with the results from the Au cathode device. After a 30nm thick TPBI (1,3,5-tris(2-N-phenylbenzimidazolyl)-benzene layer was inserted between light emitting layer and the Al cathode, the device performances were significantly enhanced. The maximum EQE and the maximum luminance reached 10.7 % and 2170 cd/m², respectively, a more than 10 fold increase compared to the devices without TPBI layer. The TPBI layer not only functioned as hole blocking layer which made holes and electrons more balanced inside the device, but also moved the recombination zone away from the cathode, thereby enhancing the device performances.

Citation Download Citation

Lei Wang, Bin Du, Yong Cao, and Jian Wang "Highly efficient red light-emitting devices using copolymer containing charged iridium complex in the side chain", Proc. SPIE 6828, Light-Emitting Diode Materials and Devices II, 68280I (20 November 2007); https://doi.org/10.1117/12.768571

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available