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Reductive Electropolymerization of a Vinyl-containing Poly-pyridyl Complex on Glassy Carbon and Fluorine-doped Tin Oxide Electrodes
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Electropolymerized Polythiophenes Bearing Pendant Nitroxide Radicals
Fei Li1, Yanpu Zhang1, Se Ra Kwon1
1Artie McFerrin Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, Texas 77843-3122, United States.
ACS Macro Letters
|May 26, 2022
Summary
We synthesized polythiophenes with pendant 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) radicals via electropolymerization. Varying alkyl spacer lengths influenced conductivity and electroactivity, offering insights into electronic material properties.
Area of Science:
- Materials Science
- Electrochemistry
- Polymer Chemistry
Background:
- Polythiophenes are conductive polymers with applications in electronics.
- Incorporating stable radicals like TEMPO can impart unique electrochemical properties.
- Controlling the radical's proximity to the polymer backbone is crucial for material performance.
Purpose of the Study:
- To develop a facile method for synthesizing polythiophenes with pendant TEMPO radicals (PTATs).
- To investigate the effect of alkyl spacer length on the electronic, electrochemical, and morphological properties of PTATs.
- To understand structure-property relationships for enhanced charge transport and energy storage.
Main Methods:
- Electropolymerization of thiophene monomers in boron trifluoride diethyl etherate (BFEE).
- Synthesis of PTATs with varying alkyl spacer lengths (n=2, 4, 6).
- Characterization using UV-vis spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, SEM, and AFM.
Main Results:
- Successful synthesis of PTATs with tunable TEMPO radical spacing.
- Longer alkyl chains (octyl) were found to suppress aggregation.
- Highest conductivity was observed for n=4, while highest electroactivity was seen for n=6.
Conclusions:
- Alkyl spacer length significantly impacts PTAT morphology, conductivity, and electroactivity.
- PTATs with optimized spacer lengths show promise for electronic and energy storage applications.
- Morphological control is key to understanding and improving charge transport in these materials.
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