Related Experiment Video
Updated: Apr 8, 2026
11:44
Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
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Predictive analysis of organic semiconductor photodegradation by FTIR spectroscopy with multivariate analysis
Sarah M Tyler1, Thomas J Blackburn1, Kellen T Schneider1
1Department of Chemistry and Biochemistry, University of Arizona, 1306 East University Boulevard, Tucson, AZ 85721, USA. pembertn@arizona.edu.
The Analyst
|April 7, 2026
Summary
Researchers developed a new method using FTIR spectroscopy and multivariate analysis to detect degradation in organic semiconductors (OSCs). This technique accurately distinguishes between pristine and degraded OSC materials, aiding in the development of more durable optoelectronic devices.
Area of Science:
- Materials Science
- Spectroscopy
- Organic Electronics
Background:
- Organic semiconductors (OSCs) are key components in advanced optoelectronic devices.
- Degradation of OSCs, contacts, and transport layers hinders long-term device performance.
- Characterizing chemical and photochemical degradation in operando requires improved diagnostic tools.
Purpose of the Study:
- To demonstrate attenuated total reflectance-FTIR (ATR-FTIR) spectroscopy with multivariate analysis as a diagnostic tool.
- To monitor the degradation 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), a model high-performance OSC.
- To assess the accuracy of multivariate analysis in identifying degraded OSC samples.
Main Methods:
- Attenuated total reflectance-FTIR (ATR-FTIR) spectroscopy was employed.
- Multivariate analysis was applied to FTIR spectral data.
- Accelerated photodegradation experiments were conducted on PTB7 thin films.
Main Results:
- ATR-FTIR combined with multivariate analysis effectively monitored degradation.
- The method accurately distinguished between pristine and degraded PTB7 samples.
- High accuracy was achieved in identifying degraded OSCs in accelerated tests.
Conclusions:
- Multivariate analysis of FTIR data is a powerful tool for assessing OSC degradation.
- This approach can identify pristine versus degraded organic semiconductor materials.
- The findings support the practical application of these diagnostics for improving OSC stability.
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