Issue 11, 2023

Origins of hydrogen peroxide selectivity during oxygen reduction on organic mixed ionic–electronic conducting polymers

Abstract

Electrochemical reduction of atmospheric oxygen provides carbon emission-free pathways for the generation of electricity from chemical fuels and for the distributed production of green chemical oxidants like hydrogen peroxide. Recently, organic mixed ionic–electronic conducting polymers (OMIECs) have been reported as a new class of active electrode materials for the oxygen reduction reaction. This work sets out to identify the operative oxygen reduction mechanism of OMIECs through a multi-faceted experimental and theoretical approach. Using a combination of pH-dependent electrochemical characterization, operando UV-Vis and Raman spectroscopy, and ab initio calculations, we find that the n-type OMIEC, p(NDI-T2 P75), displays pH-dependent activity for the selective reduction of oxygen to the 2-electron hydrogen peroxide product. We use microkinetic simulations of the electrochemical behavior to rationalize our experimental observations through a polaron-mediated, non-adsorptive pathway involving chemical reduction of oxygen to the 1-electron superoxide intermediate followed by pH-dependent catalytic disproportionation to hydrogen peroxide. Finally, this pathway is applied to understand the experimental oxygen reduction reactivity across several n- and p-type OMIECs.

Graphical abstract: Origins of hydrogen peroxide selectivity during oxygen reduction on organic mixed ionic–electronic conducting polymers

Supplementary files

Article information

Article type
Paper
Submitted
28 6月 2023
Accepted
15 9月 2023
First published
21 9月 2023

Energy Environ. Sci., 2023,16, 5409-5422

Author version available

Origins of hydrogen peroxide selectivity during oxygen reduction on organic mixed ionic–electronic conducting polymers

A. De La Fuente Durán, A. Y. Liang, I. Denti, H. Yu, D. Pearce, A. Marks, E. Penn, J. Treiber, K. Weaver, L. Turaski, I. P. Maria, S. Griggs, X. Chen, A. Salleo, W. C. Chueh, J. Nelson, A. Giovannitti and J. T. Mefford, Energy Environ. Sci., 2023, 16, 5409 DOI: 10.1039/D3EE02102E

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements