Abstract
| Original language | English |
|---|---|
| Article number | 135004 |
| Journal | Electrochimica Acta |
| Volume | 327 |
| Number of pages | 9 |
| ISSN | 0013-4686 |
| DOIs | |
| Publication status | Published - 2019 |
Keywords
- Solid oxide cells
- Infiltration
- Electrocatalytic activity
- Model for adsorption of species
- Nanoparticles
- Fuel electrodes
Cite this
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Understanding the electrocatalytic activity of transition metal nanoparticles for solid oxide cell fuel electrodes. / Drasbæk, Daniel B.; Traulsen, Marie L.; Sudireddy, Bhaskar R.; Holtappels, Peter.
In: Electrochimica Acta, Vol. 327, 135004, 2019.Research output: Contribution to journal › Journal article › Research › peer-review
TY - JOUR
T1 - Understanding the electrocatalytic activity of transition metal nanoparticles for solid oxide cell fuel electrodes
AU - Drasbæk, Daniel B.
AU - Traulsen, Marie L.
AU - Sudireddy, Bhaskar R.
AU - Holtappels, Peter
PY - 2019
Y1 - 2019
N2 - In this work, we utilized the concept of decoupling the electrocatalytic activity from the current conducting phase of solid oxide cell fuel electrodes to investigate the electrochemical performance of three different transition metals, namely Ni, Co, and Fe. It was found that the nickel and cobalt infiltrated cells had comparable performances in both 4% H2O/H2 and 50% H2O/H2. Furthermore, iron nanoparticles were found to be the better electrocatalyst at low pO2 values, however at higher pO2 values the iron infiltration became the inferior catalyst. Investigating the temperature dependence of the polarization resistance in terms of activation energy and pre-exponential factor showed interesting differences between the metal catalysts and a dependence on the gas atmosphere. The results were analyzed by developing a model based on the harmonic oscillator, the model allows for correlating changes in activation energy and pre-exponential factor with kinetic parameters of the electrode reaction. The model indicates that at higher pO2 values, iron nanoparticles experience a surface blockade, i.e. strong bonding of the reactants to the catalytic sites. For the nickel electrocatalyst, an increase in steam content according to the model leads to an increase in the turnover frequency, which is in good agreement with earlier reports in literature.
AB - In this work, we utilized the concept of decoupling the electrocatalytic activity from the current conducting phase of solid oxide cell fuel electrodes to investigate the electrochemical performance of three different transition metals, namely Ni, Co, and Fe. It was found that the nickel and cobalt infiltrated cells had comparable performances in both 4% H2O/H2 and 50% H2O/H2. Furthermore, iron nanoparticles were found to be the better electrocatalyst at low pO2 values, however at higher pO2 values the iron infiltration became the inferior catalyst. Investigating the temperature dependence of the polarization resistance in terms of activation energy and pre-exponential factor showed interesting differences between the metal catalysts and a dependence on the gas atmosphere. The results were analyzed by developing a model based on the harmonic oscillator, the model allows for correlating changes in activation energy and pre-exponential factor with kinetic parameters of the electrode reaction. The model indicates that at higher pO2 values, iron nanoparticles experience a surface blockade, i.e. strong bonding of the reactants to the catalytic sites. For the nickel electrocatalyst, an increase in steam content according to the model leads to an increase in the turnover frequency, which is in good agreement with earlier reports in literature.
KW - Solid oxide cells
KW - Infiltration
KW - Electrocatalytic activity
KW - Model for adsorption of species
KW - Nanoparticles
KW - Fuel electrodes
U2 - 10.1016/j.electacta.2019.135004
DO - 10.1016/j.electacta.2019.135004
M3 - Journal article
VL - 327
JO - Electrochimica Acta
JF - Electrochimica Acta
SN - 0013-4686
M1 - 135004
ER -