Communications
Keywords: carbene ligands · cyclometalation · luminescence ·
.
OLEDs · platinum
[
[
[
[
[
[
1] H. Yersin, Highly Efficient OLEDs with Phosphorescent Mate-
Figure 3. Construction of the device (left) and structure of the Ir
complex and compound 7 (right). ELT=electron-transport layer,
HBL=hole-blocking layer, HTL=hole transporting layer, HIL=hole
injecting layer, BCP=2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline.
6] a) J. Li, Z. Wang, E. Turner (Arizona State University, USA),
WO 2009111299, 2009; b) T. Murakami, K. Yagi, S. Ichijima, T.
Igarashi, T. Satou (Fuji Photo Film Co., Japan), WO 2006115301,
2006; c) R. Pretot, P. A. Van Der Schaaf, J. Schmidt, B. Schmid-
halter, T. Schaefer, B. Lamatsch (Ciba Specialty Chemicals
Holding Inc., Switzerland), WO 2006067074, 2006; d) M. E.
Thompson, A. Tamayo, P. Djurovich, T. Sajoto, S. R. Forrest,
P. B. Mackenzie, R. Walters, J. Brooks, X.-C. Li, B. Alleyne, J.-Y.
Tsai, C. Lin, B. Ma, M. S. Barone, R. Kwong (The University of
Southern California, USA, The Trustees of Princeton Univer-
sity; Universal Display Corporation), WO 2005113704, 2005;
e) R. Walters, P. B. MacKenzie, M. E. Thompson (USA), US
2005260445, 2005; f) M. Egen, K. Kahle, M. Bold, T. Gessner, C.
Lennartz, S. Nord, H.-W. Schmidt, M. Thelakkat, M. Baete, C.
Neuber, W. Kowalsky, C. Schildknecht, H.-H. Johannes (BASF
AG, Germany), WO 2006056418, 2006; g) O. Molt, E. Fuchs, M.
Egen, K. Kahle, C. Lennartz (BASF AG, Germany), WO
produced by thermal deposition under high vacuum con-
ditions onto a glass substrate coated with indium-tin-oxide
(
ITO), where different concentrations (6, 8, 10, and 12%) of
complex 6 were doped into the new matrix material. The CIE
Commission Internationale de l’ꢀclairage) coordinates of
.162/0.314 promise a green–blue color which could also be
(
0
observed in the experiment. Therefore 6 is a promising
candidate for the blue component in white OLEDs, as for
lighting applications a pure-blue emission is not needed.
“
Deeper blue compounds” such as 4 with CIE = 0.167/0.157
unfortunately show significantly lower quantum yields.
Independent of the dopant concentration, the electro-
luminescence spectra (see the Supporting Information) show
their maxima at 480 nm and a pronounced progression of the
emission band. The maximum luminance depends on the
doping concentration and can be found in between
2
007088093, 2007.
8] Crystallografic data for 6: C H N O Pt, M = 541.46, 0.33 ꢁ
À2
À2
[
4
1
900 cdm (13 V, 6% doping) and 6750 cdm (13.2 V,
2% doping). The maximum external quantum efficiency is
21 18
2
3
w
3
0.13 ꢁ 0.12 mm , monoclinic, P2 /c, a = 9.333(1), b = 18.052(1),
1
3
c = 11.185(2) ꢂ, b = 109.05(1)8, V= 1781.3(4) ꢂ , Z = 4, 1
=
calcd
reached at the highest doping concentration of 12%
Table 2).
À3
À1
2.019 Mgm , m = 7.902 mm , Mo-K irradiation, l = 0.71073 ꢂ,
a
(
T= 198(2) K, 18766 reflections, 3628 independent, R = 0.0767,
R = 0.0460 ([F > 2s(F )]), wR = 0.1291 (all data), GOF =
int
2
2
2
1
1
.226, V= 4.84 to 26.408. Largest diff. peak and hole 2.685 and
Table 2: Device performance.
3
À3.930 eA . CCDC 794937 contains the supplementary crystal-
lographic data for this paper. These data can be obtained free of
Doping Current density at
Voltage at
300 cdm [V] [cdm
Luminance EQE
[
a]
À2
À2
À2
À2
[a]
conc.
300 cdm [mAcm
]
]
[%]
6
8
1
1
%
%
0%
2%
3.7
3.5
3.2
2.8
8.6
8.5
8.5
8.4
4900
5000
5900
6750
5.4
5.6
6.0
6.2
[
[a] External quantum efficiency.
[
[
We were able to synthesize a new class of platinum(II)
complexes with cyclometalated 1-phenylimidazole ligands
and investigated their photophysical properties. The solid-
state structure of these compounds could be shown for
compound 6. With the exception of 3 all complexes emit in the
green–blue part of the visible spectrum and show interesting
photophysical properties.
Djurovich, M. E. Thompson, H. Yersin, Proc. SPIE 2007, 6655,
66550F1.
11] a) N. Langer, K. Kahle, C. Lennartz, O. Molt, E. Fuchs, J.
Rudolph, C. Schildknecht, S. Watanabe, G. Wagenblast (BASF
SE, Germany), WO 2009003919, 2009; b) N. Langer, K. Kahle,
C. Lennartz, O. Molt, E. Fuchs, J. Rudolph, C. Schildknecht, S.
Watanabe, G. Wagenblast (BASF SE, Germany), WO
Received: March 4, 2010
Revised: September 30, 2010
Published online: November 29, 2010
2009003898, 2009.
1
ꢀ 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2010, 49, 10214 –10216