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Elimination of hole injection barriers by conducting polymer anodes in polyfluorene light-emitting diodes

被引：38
作者：
Lane, Paul A.
Brewer, Paul J.
Huang, Jingsong
Bradley, Donal D. C.
deMello, John C.
机构：
[1] USN, Res Lab, Washington, DC 20375 USA
[2] Univ London Imperial Coll Sci Technol & Med, Dept Chem, London SW7 2AZ, England
[3] Univ London Imperial Coll Sci Technol & Med, Dept Phys, London SW7 2AZ, England
来源：
PHYSICAL REVIEW B | 2006年 / 74卷 / 12期
关键词：
ENERGY-LEVEL ALIGNMENT; ELECTRIC-FIELD; ELECTROABSORPTION SPECTROSCOPY; METAL; PERFORMANCE;
D O I：
10.1103/PhysRevB.74.125320
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
We have measured the built-in potential of a series of polyfluorene-containing light-emitting diodes (LEDs) by electroabsorption spectroscopy. When the anode incorporates a layer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), the inferred anode work function is equal to the ionization potential of the emissive polyfluorene. This result requires that the Fermi level of PEDOT:PSS is pinned to the highest occupied molecular orbital of the emissive polymer. Pinning of the anode Fermi level eliminates the injection barrier to holes and explains the low turn-on bias of polymer LEDs that incorporate PEDOT:PSS. We attribute this phenomenon to electron trapping at the interface between PEDOT:PSS and the emissive layer.
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页数：7
相关论文
共 39 条
[1]   Direct determination of the exciton binding energy of conjugated polymers using a scanning tunneling microscope [J].
Alvarado, SF ;
Seidler, PF ;
Lidzey, DG ;
Bradley, DDC .
PHYSICAL REVIEW LETTERS, 1998, 81 (05) :1082-1085
[2]  
Bernius MT, 2000, ADV MATER, V12, P1737, DOI 10.1002/1521-4095(200012)12:23<1737::AID-ADMA1737>3.0.CO
[3]  
2-N
[4]   Role of electron injection in polyfluorene-based light emitting diodes containing PEDOT:PSS -: art. no. 205209 [J].
Brewer, PJ ;
Lane, PA ;
Huang, JS ;
DeMello, AJ ;
Bradley, DDC ;
DeMello, JC .
PHYSICAL REVIEW B, 2005, 71 (20)
[5]   Internal field screening in polymer light-emitting diodes [J].
Brewer, PJ ;
Lane, PA ;
deMello, AJ ;
Bradley, DDC ;
deMello, JC .
ADVANCED FUNCTIONAL MATERIALS, 2004, 14 (06) :562-570
[6]   Built-in field electroabsorption spectroscopy of polymer light-emitting diodes incorporating a doped poly(3,4-ethylene dioxythiophene) hole injection layer [J].
Brown, TM ;
Kim, JS ;
Friend, RH ;
Cacialli, F ;
Daik, R ;
Feast, WJ .
APPLIED PHYSICS LETTERS, 1999, 75 (12) :1679-1681
[7]   Film morphology and photophysics of polyfluorene [J].
Cadby, AJ ;
Lane, PA ;
Mellor, H ;
Martin, SJ ;
Grell, M ;
Giebeler, C ;
Bradley, DDC ;
Wohlgenannt, M ;
An, C ;
Vardeny, ZV .
PHYSICAL REVIEW B, 2000, 62 (23) :15604-15609
[8]   Dispersive electron transport in an electroluminescent polyfluorene copolymer measured by the current integration time-of-flight method [J].
Campbell, AJ ;
Bradley, DDC ;
Antoniadis, H .
APPLIED PHYSICS LETTERS, 2001, 79 (14) :2133-2135
[9]   Controlling Schottky energy barriers in organic electronic devices using self-assembled monolayers [J].
Campbell, IH ;
Rubin, S ;
Zawodzinski, TA ;
Kress, JD ;
Martin, RL ;
Smith, DL ;
Barashkov, NN ;
Ferraris, JP .
PHYSICAL REVIEW B, 1996, 54 (20) :14321-14324
[10]   Direct measurement of conjugated polymer electronic excitation energies using metal/polymer/metal structures [J].
Campbell, IH ;
Hagler, TW ;
Smith, DL ;
Ferraris, JP .
PHYSICAL REVIEW LETTERS, 1996, 76 (11) :1900-1903
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