Blue fluorescent OLED materials and their application for high-performance devices

Abstract The authors applied two technologies to improve the efficiency of fluorescent blue organic light-emitting diodes (OLEDs). First, an efficiency-enhancement layer (EEL) was introduced to boost triplet–triplet fusion (TTF). Second, new blue dopants with a higher orientation factor in the emitting layer were developed. Consequently, the external quantum efficiency (EQE) was increased up to 11.5% with Commission Internationale de l’Eclairage (CIE) 1931 color coordinates of (0.138, 0.092). The reported results may lead to EQEs that exceed 14% with fluorescent blue emitters.

[2]  Toshinari Ogiwara,et al.  37.2: Efficiency Improvement of Fluorescent Blue Device by Molecular Orientation of Blue Dopant , 2013 .

[3]  Tadashi Kusumoto,et al.  Highly efficient blue electroluminescence from a distyrylarylene emitting layer with a new dopant , 1995 .

[4]  D. Yokoyama.  Molecular orientation in small-molecule organic light-emitting diodes , 2011 .

[5]  Wolfgang Brütting,et al.  Increased light outcoupling efficiency in dye-doped small molecule organic light-emitting diodes with horizontally oriented emitters , 2011 .

[6]  P. Meredith,et al.  Electronic and optoelectronic materials and devices inspired by nature , 2013, Reports on progress in physics. Physical Society.

[7]  C. Tang,et al.  Organic Electroluminescent Diodes , 1987 .

[8]  W. Barnes,et al.  Light outcoupling efficiency of top-emitting organic light-emitting diodes , 2004 .

[9]  H. Kuma,et al.  39.4: Highly Efficient Fluorescent Blue OLEDs with Efficiency‐enhancement Layer , 2010 .

[10]  K. Fukuoka,et al.  17.1: Invited Paper: Improvement of Lifetime in Organic Electroluminescence , 2004 .

[11]  M. Scarselli,et al.  Electronic and optoelectronic nano-devices based on carbon nanotubes , 2012, Journal of physics. Condensed matter : an Institute of Physics journal.

[12]  Tukaram K. Hatwar,et al.  Triplet annihilation exceeding spin statistical limit in highly efficient fluorescent organic light-emitting diodes , 2009 .

[13]  R. Naraoka,et al.  56.4: New Deep Blue Fluorescent Materials and Their Application to High Performance OLEDs , 2011 .

[14]  Jun-ichi Takahashi,et al.  Degradation Analysis of Blue Phosphorescent Organic Light Emitting Diode by Impedance Spectroscopy and Transient Electroluminescence Spectroscopy , 2009, IEICE Trans. Electron..

[15]  R. Weisman,et al.  Determination of Triplet Quantum Yields from Triplet−Triplet Annihilation Fluorescence , 2000 .

[16]  Wolfgang Brütting,et al.  Determination of molecular dipole orientation in doped fluorescent organic thin films by photoluminescence measurements , 2010 .

[17]  Tukaram K. Hatwar,et al.  30.4: High‐Efficiency Fluorescent Red‐ and Yellow‐Emitting OLED Devices , 2009 .

[18]  K. Fukuoka,et al.  47.3: Highly Efficient Fluorescent Deep Blue Dopant for “Super Top Emission” Device , 2008 .