Enhanced performance of blue OLED with water/alcohol soluble conjugated polymer as electron injection layer
Document Type
Article
Publication Date
2-1-2021
Abstract
In this work, a water/alcohol-soluble conjugated polymer poly (9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dih exylfluorene)] (PFNC6) is synthesized and the photophysical properties are investigated. Subsequently, it is tested as electron injection layer in a blue emitting OLED with PFO. The maximum current efficiency (CE) and external quantum efficiency (EQE) of the device increased by 3 times to 0.75 cd/A and 0.66%. Further enhancement in the OLED performance is obtained when a bilayer electron injection consisting of PFNC6 and LiF are used where the maximum CE is 2.16 cd/A and the maximum EQE is 1.55%. Measurement with electron-only-devices confirmed that the electron mobility is increased for the device with PFNC6 as compared to the control device. Furthermore, higher V-bi is obtained in photovoltaic measurement when PFNC6 is used. As a result, the electron injection barrier is reduced and electron injection is more efficient.
Keywords
OLED, Water/alcohol soluble conjugated polymer, Electron injection layer, Electron injection barrier, Interface dipole, Spin coating
Divisions
Science
Funders
Ministry of Education, Malaysia[FRGS/1/2019/STG07/MMU/02/1],Ministry of Science and Technology of Taiwan (MOST)
Publication Title
Synthetic Metals
Volume
272
Publisher
Elsevier Science SA
Publisher Location
PO BOX 564, 1001 LAUSANNE, SWITZERLAND