Abstract

A Spectro electrochemical cell is described that enables confocal Raman microscopy studies of electrode-supported films. the confocal probe volume (∼1 μm3) was treated as a fixed-volume reservoir for the observation of potential-induced changes in chemical composition at microscopic locations within an ∼20 μm thickness layer of a redox polymer cast onto a 3 mm diameter carbon disk electrode. using a Raman system with high collection efficiency and wavelength reproducibility, spectral subtraction achieved excellent rejection of background interferences, opening opportunities for measuring within micrometer-scale thickness redox films on widely available, low-cost, and conventional carbon disk electrodes. the cell performance and spectral difference technique are demonstrated in experiments that detect transformations of redox-active molecules exchanged into electrode-supported ionomer membranes. then in situ measurements were sensitive to changes in the film oxidation state and swelling/deswelling of the polymer framework in response to the uptake and discharge of charge-compensating electrolyte ions. the studies lay a foundation for confocal Raman microscopy as a quantitative in situ probe of processes within electrode-immobilized redox polymers under development for a range of applications, including electrosynthesis, energy conversion, and chemical sensing.

Department(s)

Chemistry

Publication Status

Open Access

Comments

National Science Foundation, Grant CBET-1921075

Keywords and Phrases

confocal; polymer-modified electrode; Raman microscopy; redox polymer; thin film

International Standard Serial Number (ISSN)

2694-250X

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2025 American Chemical Society, All rights reserved.

Creative Commons Licensing

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

Publication Date

19 Apr 2023

Included in

Chemistry Commons

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