Journal Article

IMPULSE-2023-00146

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png In‐situ study of degradation in PTB7 : PCBM films prepared with the binary solvent additive DPE : DIO

Schwaiger, D. M.TUM* ; Lohstroh, W.MLZ* ; Wolf, M.MLZ* ; Garvey, C. J.MLZ* ; Müller-Buschbaum, P. (Corresponding author)MLZ*

2023
Wiley Hoboken, NJ

Please use a persistent id in citations: doi:10.1002/pol.20230072

Abstract: Blend films of poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b']dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7)in combination with 6,6-phenyl-C61-butyric-acid-methyl-ester (PCBM) are amodel system for low bandgap organic photovoltaics. Typically, solvent additivesare used to improve the power conversion efficiencies of the resulting devicesbut possibly also decrease the device stability. In this study, we use the binarysolvent additive 1,8-diiodooctane:diphenylether (DIO:DPE) for PTB7:PCBMblend films and study how different film drying procedures influence the physicaland chemical stability of the polymer blend. The strong influence of thedrying procedure on the stability against photoinduced degradation of thePTB7:PCBM films, produced with solvent additives, is shown with data fromUV–visible (UV–vis), Fourier transform infrared (FTIR) and Raman spectroscopy.The addition of solvent additive molecules DIO:DPE to the PTB7:PCBMblend accelerates the degradation compared with the pristine blend. At higherannealing temperature a removal of the additives is bringing degradation backto the level of the pristine blend films, which is promising for photovoltaicapplications.

Keyword(s): Energy (1st) ; Soft Condensed Matter (2nd) ; Chemistry (2nd)

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Contributing Institute(s):

1. TOFTOF (TOFTOF)
2. Heinz Maier-Leibnitz Zentrum (MLZ)

Research Program(s):

1. DFG project G:(GEPRIS)390776260 - EXC 2089: e-conversion (390776260) (390776260)

Experiment(s):

1. TOFTOF: Cold neutron time-of-flight spectrometer (NL2au)

Appears in the scientific report 2023

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Database coverage:
; Clarivate Analytics Master Journal List ; Current Contents - Physical, Chemical and Earth Sciences ; IF < 5 ; JCR ; SCOPUS ; Web of Science Core Collection

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