Innovative Strategy for Developing PEDOT Composite Scaffold for Reversible Oxygen Reduction Reaction

TL;DR

This paper introduces a new PEDOT composite scaffold for metal–air batteries that shows good thermal stability and reversible oxygen reduction reaction performance.

Contribution

The novel contribution is the development of a PEDOT–OIPC composite scaffold with high Coulombic efficiency for reversible ORR.

Findings

PEDOT–OIPC scaffolds showed 60% Coulombic efficiency in aqueous medium after 200 cycles.

The composite demonstrated good thermal stability up to 200 °C.

The scaffold structure enhances contact area for optimized redox and conduction processes.

Abstract

Metal–air batteries are an emerging technology
with great
potential to satisfy the demand for energy in high-consumption applications.
However, this technology is still in an early stage, facing significant
challenges such as a low cycle life that currently limits its practical
use. Poly(3,4-ethylenedioxythiophene) (PEDOT) conducting polymer
has already demonstrated its efficiency as catalyst for oxygen reduction
reaction (ORR) discharge as an alternative to traditional expensive
and nonsustainable metal catalysts. Apart from that, in most electrochemical
processes, three phenomena are needed: redox activity and electronic
and ionic conduction. Material morphology is important to maximize
the contact area and optimize the 3 mechanisms to obtain high-performance
devices. In this work, porous scaffolds of PEDOT–organic ionic
plastic crystal (OIPC) are prepared through vapor phase polymerization
to be used as porous self-standing cathodes. The scaffolds, based
on abundant elements, showed good thermal stability (200 °C),
with potential ORR reversible electrocatalytic activity: 60% of Coulombic
efficiency in aqueous medium after 200 cycles.

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