We examined photoinduced charge-generation dynamics of the poly(3-hexylthiophene) (P3HT)/titanyl phthalocyanine (TiOPc) bilayer and the P3HT/TiOPc/C60 trilayer using the combination of flash-photolysis time-resolved microwave conductivity experiments (fp-TRMC) and classic pump-probe transient absorption (TA) spectroscopy following dominant excitation of the P3HT layer. The superlinear increase of φΣμ for the P3HT/TiOPc bilayer, compared to the φΣμ sum of each P3HT and TiOPc layer suggest photoinduced carrier-generation. Furthermore, the superlinear increase of φΣμ of the P3HT/TiOPc/C60 trilayer with respect to the each P3HT/TiOPc and TiOPc/C60 bilayers evinces charge migration from one interface to the other interface. In addition, with selective photoexcitation on the P3HT layer, both amorphous and H-aggregated P3HT domains participate in electron transfer ([P3HT∗/TiOPc]→[P3HT•+/TiOPc•-]), contrasting to the previous observation where with selective excitation of the TiOPc layer, only the H-aggregated P3HT domain involves in hole transfer ([P3HT/TiOPc→[P3HT•+/TiOPc•-]) to produce P3HT•+/TiOPc•- in J. Phys. Chem. B 119(24), 7729 - 7739 (2015). These results under different excitation conditions are consistent with calculated energetic driving force (ΔECS) for charge generation which is -0.58 eV and -0.73 eV for amorphous and H-aggregated P3HT domains under the P3HT layer excitation, while 0.04 eV and -0.11 eV for amorphous and H-aggregated P3HT domains under the TiOPc layer excitation.
|Title of host publication||Physical Chemistry of Interfaces and Nanomaterials XIV|
|Editors||Eric R. Bittner, Sophia C. Hayes|
|State||Published - 2015|
|Event||Physical Chemistry of Interfaces and Nanomaterials XIV - San Diego, United States|
Duration: 9 Aug 2015 → 12 Aug 2015
|Name||Proceedings of SPIE - The International Society for Optical Engineering|
|Conference||Physical Chemistry of Interfaces and Nanomaterials XIV|
|Period||9/08/15 → 12/08/15|
Bibliographical notePublisher Copyright:
© 2015 SPIE.
- and photoinduced electron transfer
- carrier dynamics
- excited-state dynamics
- transient absorption spectroscopy
- Transient microwave conductivity