In Situ Spectroelectrochemical-Conductance Measurements as an Efficient Tool for the Evaluation of Charge Trapping in Conducting Polymers

• Published in: The journal of physical chemistry letters 2021-10, Vol.12 (42), p.10422-10428
• Main Authors: Nicolini, Tommaso, Marquez, Ariana Villarroel, Goudeau, Bertrand, Kuhn, Alexander, Salinas, Gerardo
• Format: Article
• Language: English
• Subjects: Physical Insights into Materials and Molecular Properties
• ISSN: 1948-7185; 1948-7185
• DOI: 10.1021/acs.jpclett.1c03108

In situ UV–vis–NIR spectroelectrochemistry has been intensively used to evaluate the electronic transitions during the charging/discharging process of π-conjugated polymers. However, the type of charge carrier and the mechanisms of their transport, remains still a point of discussion. Herein, the coupling between UV–vis–NIR spectroscopy and in situ electrochemical-conductance measurements is proposed to compare the doping process of three different thiophene-based conducting polymers. The simultaneous monitoring of electrical and absorption properties, associated with low energy electronic transitions characteristic for polarons and bipolarons, was achieved. In addition, this method allows evaluating the reversible charge trapping mechanism of poly-3,4-o-xylendioxythiophene (PXDOT), caused by the formation of σ-dimers, making it a very useful tool to determine relevant physicochemical properties of conductive materials.