Acceleration of Singlet Fission in an Aza-Derivative of TIPS-Pentacene.
The influence of the carbon to nitrogen substitution on the photoinduced dynamics of TIPS-pentacene was investigated by ultrafast transient absorption measurements on spin-coated thin films in the visible and in the near-infrared spectral region. A global target analysis was performed to provide a detailed picture of the excited-state dynamics. We found that the chemical modification has a high impact on the triplet formation and leads to shorter dynamics; hence it speeds up the singlet fission process. A faster relaxation from the singlet into the triplet manifold implies a higher efficiency because other relaxation channels are avoided. The air-stable aza-derivatives have the potential to exceed the energy conversion efficiency of TIPS-pentacene.
†Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany.
Julia
J
Herz
†Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany.
Tiago
T
Buckup
‡Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.
Fabian
F
Paulus
‡Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.
Jens
J
Engelhart
‡Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, D-69120 Heidelberg, Germany.|§Centre of Advanced Materials, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 225, D-69120 Heidelberg, Germany.
Uwe H F
UH
Bunz
†Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany.|§Centre of Advanced Materials, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 225, D-69120 Heidelberg, Germany.
Marcus
M
Motzkus
organic electronics; pentacene-based materials; quantum efficiency; transient absorption; ultrafast triplet formation