Pentafluorophenoxy boron subphthalocyanine as a fluorescent dopant emitter in organic light emitting diodes.
A fluorinated phenoxy boron subphthalocyanine (BsubPc) is shown to function as a fluorescent dopant emitter in small molecule organic light emitting diodes (OLEDs). Narrow electroluminescence (EL) emission with a full width at half-maximum of ∼30 nm was observed regardless of the host used, indicating that this narrow EL is intrinsic to the BsubPc molecule. A bathochromic shift and the growth of a new EL peak at higher wavelengths with increasing doping concentration were found to be a result of molecular aggregation. Excitation of BsubPc by direct charge trapping as well as Förster resonant energy transfer were shown using different host molecules. A maximum efficiency of 1.5 cd/A was achieved for a 4,4'-N,N'-dicarbazole-biphenyl (CBP) host.
Helander
Michael G
MG
Department of Materials Science and Engineering, University of Toronto, 184 College St., Toronto, Ontario, Canada.
Morse
Graham E
GE
Qiu
Jacky
J
Castrucci
Jeffrey S
JS
Bender
Timothy P
TP
Lu
Zheng-Hong
ZH