Probing Inter- and Intrachain Exciton Coupling in Isolated Poly(3-hexylthiophene) Nanofibers: Effect of Solvation and Regioregularity.
We report wavelength and time-resolved photoluminescence studies of isolated extended (1-10 μm length) poly(3-hexylthiophene) (P3HT) nanofibers (xNFs) cast on glass from suspension. The PL spectra of xNFs show multiple vibronic replicas that appear to be associated with the existence of both H- and J-type aggregates. The PL spectra of xNFs made from regioregular (rr)- (93%) and highly regioregular (hrr)-P3HT (98%) both show similarities in PL spectra suggestive of common chain packing features, as well as subtle differences that can be attributed to higher long-range order in the hrr-xNFs. Specifically, PL spectral measurements on isolated xNFs made from highly regioregular (>98%) P3HT showed a red-shifted electronic origin (≈30 meV) and increased 0-0/0-1 PL intensity ratio for the J-type species, suggestive of enhanced structural coherence length and intrachain order.
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Mina
M
Baghgar
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Joelle
J
Labastide
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Felicia
F
Bokel
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Irene
I
Dujovne
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Aidan
A
McKenna
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Austin M
AM
Barnes
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Emily
E
Pentzer
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Todd
T
Emrick
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Ryan
R
Hayward
†Department of Physics, ‡Department of Chemistry, §Polymer Science and Engineering, and ∥Department of Chemical Engineering, University of Massachusetts-Amherst, Amherst, MA 01003, United States.
Michael D
MD
Barnes
H/J-type aggregates; isolated P3HT nanofibers; organic photovoltaics; photoluminescence spectra