TY - JOUR
T1 - Revealing the Singlet Fission Mechanism for a Silane-Bridged Thienotetracene Dimer
AU - Lin, Liang Chun
AU - Dill, Ryan D.
AU - Thorley, Karl J.
AU - Parkin, Sean R.
AU - Anthony, John E.
AU - Johnson, Justin C.
AU - Damrauer, Niels H.
N1 - Publisher Copyright:
© 2024 The Authors. Published by American Chemical Society.
PY - 2024/5/23
Y1 - 2024/5/23
N2 - Tetraceno[2,3-b]thiophene is regarded as a strong candidate for singlet fission-based solar cell applications due to its mixed characteristics of tetracene and pentacene that balance exothermicity and triplet energy. An electronically weakly coupled tetraceno[2,3-b]thiophene dimer (Et2Si(TIPSTT)2) with a single silicon atom bridge has been synthesized, providing a new platform to investigate the singlet fission mechanism involving the two acene chromophores. We study the excited state dynamics of Et2Si(TIPSTT)2 by monitoring the evolution of multiexciton coupled triplet states, 1TT to 5TT to 3TT to T1 + S0, upon photoexcitation with transient absorption, temperature-dependent transient absorption, and transient/pulsed electron paramagnetic resonance spectroscopies. We find that the photoexcited singlet lifetime is 107 ps, with 90% evolving to form the TT state, and the complicated evolution between the multiexciton states is unraveled, which can be an important reference for future efforts toward tetraceno[2,3-b]thiophene-based singlet fission solar cells.
AB - Tetraceno[2,3-b]thiophene is regarded as a strong candidate for singlet fission-based solar cell applications due to its mixed characteristics of tetracene and pentacene that balance exothermicity and triplet energy. An electronically weakly coupled tetraceno[2,3-b]thiophene dimer (Et2Si(TIPSTT)2) with a single silicon atom bridge has been synthesized, providing a new platform to investigate the singlet fission mechanism involving the two acene chromophores. We study the excited state dynamics of Et2Si(TIPSTT)2 by monitoring the evolution of multiexciton coupled triplet states, 1TT to 5TT to 3TT to T1 + S0, upon photoexcitation with transient absorption, temperature-dependent transient absorption, and transient/pulsed electron paramagnetic resonance spectroscopies. We find that the photoexcited singlet lifetime is 107 ps, with 90% evolving to form the TT state, and the complicated evolution between the multiexciton states is unraveled, which can be an important reference for future efforts toward tetraceno[2,3-b]thiophene-based singlet fission solar cells.
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U2 - 10.1021/acs.jpca.4c01463
DO - 10.1021/acs.jpca.4c01463
M3 - Article
C2 - 38717589
AN - SCOPUS:85193212776
SN - 1089-5639
VL - 128
SP - 3982
EP - 3992
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 20
ER -