High-performance hole-transport polyurethanes for light-emitting diodes applications
Kuo, CHui; Peng, KC; Kuo, LiC; Yang, KHui; Lee, JHaw; Leung, Mankit; Hsieh, KuoH
| HERO ID | 2893020 |
|---|---|
| In Press | No |
| Year | 2006 |
| Title | High-performance hole-transport polyurethanes for light-emitting diodes applications |
| Authors | Kuo, CHui; Peng, KC; Kuo, LiC; Yang, KHui; Lee, JHaw; Leung, Mankit; Hsieh, KuoH |
| Journal | Chemistry of Materials |
| Volume | 18 |
| Issue | 17 |
| Page Numbers | 4121-4129 |
| Abstract | A novel family of hole-transport polyurethanes (PUs) has been developed. The PUs were prepared from the condensation polymerization of isophorone diisocyanate (IPDI) with ( E, E)-1,4-bis(2-hydroxystyryl) benzene, an oligo p-phenylene-(E)-vinylene (OPV) unit, and various amounts of 2,5-bis(4-hydroxyphenyl)- 1,3,4-oxadiazole (OXD), as well as with 4-tert-butyl phenol as the terminal group. The PUs demonstrates superior properties that were concluded on the basis of the improved current injection in the corresponding hole-only device. The OLED device with the OPV-PU interfacial layer inserted in ITO/PEDOT: PSS(20 nm)/ PU(30 nm)/alpha-NPB(10 nm)/Bebq(2)(20 nm)/ Ca(10 nm)/ Ag(100 nm) has a dramatic voltage reduction of 2.5 V under the current density of 100 mA/cm(2). When compared to the control device, the current efficiency was improved 2.37 times. The maximum brightness increased to 14900 cd/m(2) in comparison to that of 5780 cd/m(2) for the control device. The performance of the OLED devices was fine-tuned by adjusting the combination of the OPV and OXD units to reach electron-hole balanced conditions. The maximum current efficiency increased to 4.12 cd/A at 5.5 V when the PU layer of OPV: OXD = 67: 33 was used. |
| Doi | 10.1021/cm060124w |
| Wosid | WOS:000239758300028 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |