In-situ monitoring of molecular vibrations of two organic semiconductors in photovoltaic blends and their impact on thin film morphology
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
We report in-situ simultaneous monitoring of molecular vibrations of two components in organic photovoltaic blends using resonant Raman spectroscopy. Blend films were composed of a low bandgap copolymer thieno[3,2-b]thiophene-diketopyrrolopyrrole (DPPTTT) and (6,6)-phenyl-C71-butyric acid ester (PC 70BM). Changes in Raman spectra associated with crystallization processes of each component and their impact on thin film morphology were studied during thermal annealing and cooling processes. Transition temperatures to crystalline phases in blends were measured at ∼150 °C and ∼170 °C for DPPTTT and PC 70BM, respectively. Such phase changes lead to modifications in local chemical composition reducing relative Raman peak intensities (IPC70BM/IDPPTTT) from ∼0.4 in PC 70BM-rich domains to ∼0.15 in homogeneous areas.
Date Issued
2013-04-29
Date Acceptance
2013-04-12
Citation
Applied Physics Letters, 2013, 102 (17)
ISSN
1077-3118
Publisher
AIP Publishing
Journal / Book Title
Applied Physics Letters
Volume
102
Issue
17
Copyright Statement
© 2013 AIP Publishing LLC. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in Applied Physics Letters and may be found at http://dx.doi.org/10.1063/1.4803912.
Subjects
Science & Technology
Physical Sciences
Physics, Applied
Physics
PHYSICS, APPLIED
MICRO-RAMAN SPECTROSCOPY
SOLAR-CELL APPLICATIONS
POLYMER
DIODES
ORDER
Applied Physics
09 Engineering
02 Physical Sciences
Publication Status
Published
Article Number
173302