A material possessing a very small energy gap between its singlet and triplet excited states, , which allows efficient up-conversion of triplet excitons into a singlet state and leads to efficient thermally activated delayed fluorescence (TADF), is reported. The compound, 2-biphenyl-4,6-bis(12-phenylindolo[2,3-a] carbazole-11-yl)-1,3,5-triazine, breaks the restriction of a large energy gap, with a of just 0.11 eV, while maintaining a high fluorescent radiative decay rate . The intense TADF provides a pathway for highly efficient electroluminescence.
REFERENCES
1.
M. A.
Baldo
, D. F.
O’Brien
, Y.
You
, A.
Shoustikov
, S.
Sibley
, M. E.
Thompson
, and S. R.
Forrest
, Nature (London)
395
, 151
(1998
).2.
C.
Adachi
, M. A.
Baldo
, M. E.
Thompson
, and S. R.
Forrest
, J. Appl. Phys.
90
, 5048
(2001
).3.
4.
D.
Kondakov
, T. D.
Pawlik
, T. K.
Hatwar
, and J. P.
Spindler
, J. Appl. Phys.
106
, 124510
(2009
).5.
C. T.
Brown
and D.
Kondakov
, J. Soc. Inf. Disp.
12
, 323
(2004
).6.
7.
L.
Brand
and B.
Witholt
, Methods Enzymol.
11
, 776
(1967
).8.
F. A.
Salazar
, A.
Fedorav
, and M. N.
Bereran-Santos
, Chem. Phys. Lett.
271
, 361
(1997
).9.
10.
A.
Endo
, M.
Ogasawara
, A.
Takahashi
, D.
Yokoyama
, Y.
Kato
, and C.
Adachi
, Adv. Mater.
21
, 4802
(2009
).11.
J. C.
Deaton
, S. C.
Switalski
, D. Y.
Kondakov
, R. H.
Young
, T. D.
Pawlik
, D. J.
Giesen
, S. B.
Harkins
, A. J. M.
Miller
, S. F.
Mickenberg
, and J. C.
Peters
, J. Am. Chem. Soc.
132
, 9499
(2010
).12.
J.
Saltiel
, J. Am. Chem. Soc.
92
, 410
(1970
).13.
14.
N. J.
Turro
, Modern Molecular Photochemistry
(University Science Books
, Sausalito
, 1991
), p. 91
.15.
A.
Endo
and C.
Adachi
, Chem. Phys. Lett.
460
, 155
(2008
).16.
R.
Englman
, Mol. Phys.
18
, 145
(1970
).17.
See supplementary material at http://dx.doi.org/10.1063/1.3558906 for synthetic procedure.
© 2011 American Institute of Physics.
2011
American Institute of Physics
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