TY - GEN
T1 - Highly Efficient Electron-Transporting Polymers for Light-EmittingDiodes
AU - Liu, Michelle S.
AU - Jiang, Xuezhong
AU - Herguth, Petra
AU - Jen, Alex K.-Y.
N1 - Publication details (e.g. title, author(s), publication statuses and dates) are captured on an “AS IS” and “AS AVAILABLE” basis at the time of record harvesting from the data source. Suggestions for further amendments or supplementary information can be sent to [email protected].
PY - 2001
Y1 - 2001
N2 - A series of well-defined oligomers were synthesized to provide insight on the effect of the position of cyano substituents on the electronic properties of conjugated molecules and polymers. Two copolymers PF3CNP1 and PF1CNP1 composed of 9,9-di-n-hexylfluorene and 2,5-dicyanobenzene have been synthesized based on this model study. By attaching two electron-withdrawing cyano groups onto the phenylene ring, the electron affinity and electron transporting ability of polyfluorenes are greatly enhanced. The devices employing a conducting polymer, poly(3,4-ethylene dioxythiophene) (PEDOT) as the hole injecting layer, and the cyano-containing copolymers as the emitting and electron-transporting layer showed a much improved electroluminescence (EL) efficiency and brightness compared to that of the homopolymer, poly(9,9-di-n-hexylfluorene) (PHF) with the same device configuration. It is ascribed to the smaller energy barrier for electron injection and higher electron mobility due to increased electron affinity of the polymers through the cyano substituents. The device based on PF3CNP1 has the best performance with a low turn-on voltage (3.4 V), bright blue emission (5430 cd/m at a bias voltage of 7.4 V), and a maximum external quantum efficiency of 0.50 % due to both optimized electron affinity and charge carrier mobility.
AB - A series of well-defined oligomers were synthesized to provide insight on the effect of the position of cyano substituents on the electronic properties of conjugated molecules and polymers. Two copolymers PF3CNP1 and PF1CNP1 composed of 9,9-di-n-hexylfluorene and 2,5-dicyanobenzene have been synthesized based on this model study. By attaching two electron-withdrawing cyano groups onto the phenylene ring, the electron affinity and electron transporting ability of polyfluorenes are greatly enhanced. The devices employing a conducting polymer, poly(3,4-ethylene dioxythiophene) (PEDOT) as the hole injecting layer, and the cyano-containing copolymers as the emitting and electron-transporting layer showed a much improved electroluminescence (EL) efficiency and brightness compared to that of the homopolymer, poly(9,9-di-n-hexylfluorene) (PHF) with the same device configuration. It is ascribed to the smaller energy barrier for electron injection and higher electron mobility due to increased electron affinity of the polymers through the cyano substituents. The device based on PF3CNP1 has the best performance with a low turn-on voltage (3.4 V), bright blue emission (5430 cd/m at a bias voltage of 7.4 V), and a maximum external quantum efficiency of 0.50 % due to both optimized electron affinity and charge carrier mobility.
UR - https://www.scopus.com/pages/publications/84989190827
UR - https://www.scopus.com/pages/publications/84989190827#tab=impact
U2 - 10.1364/otf.2001.omb1
DO - 10.1364/otf.2001.omb1
M3 - RGC 32 - Refereed conference paper (with host publication)
SN - 9781557528209
T3 - Optics InfoBase Conference Papers
SP - 110
EP - 114
BT - Organic Thin Films, OTF 2001
PB - Optica Publishing Group
T2 - 2001 Optical Society of America (OSA) Syposium on Organic Thin Films for Photonics Applications, OTF 2001
Y2 - 15 October 2001 through 15 October 2001
ER -