TY - JOUR
T1 - Temperature dependence of photoluminescence properties in a thermally activated delayed fluorescence emitter
AU - Niwa, Akitsugu
AU - Kobayashi, Takashi
AU - Nagase, Takashi
AU - Goushi, Kenichi
AU - Adachi, Chihaya
AU - Naito, Hiroyoshi
PY - 2014/5/26
Y1 - 2014/5/26
N2 - Using steady-state and time-resolved photoluminescence (PL) spectroscopy, we have investigated the temperature dependence of PL properties of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN), which have a small energy gap between its singlet and triplet excited states and thus exhibits efficient thermally activated delayed fluorescence [H. Uoyama et al., Nature 492, 235 (2012)]. Below around 100 K, PL quantum efficiency of 4CzIPN thin films is largely suppressed and strong photoexcitation intensity dependence appears. These features can be explained by using rate equations for the densities of singlet and triplet excited states considering a triplet-triplet annihilation process.
AB - Using steady-state and time-resolved photoluminescence (PL) spectroscopy, we have investigated the temperature dependence of PL properties of 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyano-benzene (4CzIPN), which have a small energy gap between its singlet and triplet excited states and thus exhibits efficient thermally activated delayed fluorescence [H. Uoyama et al., Nature 492, 235 (2012)]. Below around 100 K, PL quantum efficiency of 4CzIPN thin films is largely suppressed and strong photoexcitation intensity dependence appears. These features can be explained by using rate equations for the densities of singlet and triplet excited states considering a triplet-triplet annihilation process.
UR - http://www.scopus.com/inward/record.url?scp=84901751030&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84901751030&partnerID=8YFLogxK
U2 - 10.1063/1.4878397
DO - 10.1063/1.4878397
M3 - Article
AN - SCOPUS:84901751030
SN - 0003-6951
VL - 104
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 21
M1 - 213303
ER -