Theory of the electrostatic surface potential and intrinsic dipole moments at the mixed ionic electronic conductor (MIEC)–gas interface
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
The local activation overpotential describes the electrostatic potential shift away from equilibrium at an electrode/electrolyte interface. This electrostatic potential is not entirely satisfactory for describing the reaction kinetics of a mixed ionic–electronic conducting (MIEC) solid-oxide cell (SOC) electrode where charge transfer occurs at the electrode–gas interface. Using the theory of the electrostatic potential at the MIEC–gas interface as an electrochemical driving force, charge transfer at the ceria–gas interface has been modelled based on the intrinsic dipole potential of the adsorbate. This model gives a physically meaningful reason for the enhancement in electrochemical activity of a MIEC electrode as the steam and hydrogen pressure is increased in both fuel cell and electrolysis modes. This model was validated against operando XPS data from previous literature to accurately predict the outer work function shift of thin film Sm0.2Ce0.8O1.9 in a H2/H2O atmosphere as a function of overpotential.
Date Issued
2021-07-21
Date Acceptance
2021-05-07
Citation
Physical Chemistry Chemical Physics, 2021, 23 (27), pp.14569-14579
ISSN
1463-9076
Publisher
Royal Society of Chemistry
Start Page
14569
End Page
14579
Journal / Book Title
Physical Chemistry Chemical Physics
Volume
23
Issue
27
Copyright Statement
© the Owner Societies 2021. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence.
License URL
Sponsor
Ceres Power Ltd
Engineering and Physical Sciences Research Council
Engineering & Physical Science Research Council (EPSRC)
Identifier
https://pubs.rsc.org/en/content/articlelanding/2021/CP/D1CP01639C#!divAbstract
Grant Number
PO20001949
EP/L015277/1
EP/R002010/1
Subjects
Science & Technology
Physical Sciences
Chemistry, Physical
Physics, Atomic, Molecular & Chemical
Chemistry
Physics
CURRENT-VOLTAGE CHARACTERISTICS
STABILIZED ZIRCONIA ANODES
GADOLINIUM-DOPED CERIA
HYDROGEN OXIDATION
CHARGE-TRANSFER
PARTIAL-PRESSURE
CURRENT-DENSITY
CO OXIDATION
WATER
KINETICS
Chemical Physics
02 Physical Sciences
03 Chemical Sciences
09 Engineering
Publication Status
Published
Date Publish Online
2021-05-07