TY - JOUR
T1 - Operando Characterization of Porous Nickel Foam Water Splitting Electrodes Using Near-Ambient Pressure X-ray Photoelectron Spectroscopy
AU - Chalil Oglou, Ramadan
AU - Frederiksen, Morten Linding
AU - Sun, Zhaozong
AU - Ceccato, Marcel
AU - Shavorskiy, Andrey
AU - Lauritsen, Jeppe Vang
N1 - Publisher Copyright:
© 2025 American Chemical Society.
PY - 2025/4/10
Y1 - 2025/4/10
N2 - This study presents a practical approach for characterizing industrial water-splitting nickel foam electrodes under both cathodic and anodic conditions by employing synchrotron radiation near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS). The in situ studies reveal quantitatively reduced and oxidized Ni species on the electrode surface by recording the Ni 2p3/2 signals after cycling the potential in cathodic and anodic regions, respectively. Operando studies demonstrate that a stable electrolyte film forms, allowing the probing of the solid/liquid interface under applied potentials. We attribute this stability to capillary forces within the porous structure of the foam, which enables the monitoring of surface deprotonation under anodic potentials and surface protonation under cathodic potentials. Given that the most common industrial alkaline water electrolyzer electrodes are based on nickel foams similar to the samples measured in this study, the demonstrated method offers a valuable approach for fundamental NAP-XPS examination directly on industrially employed electrodes.
AB - This study presents a practical approach for characterizing industrial water-splitting nickel foam electrodes under both cathodic and anodic conditions by employing synchrotron radiation near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS). The in situ studies reveal quantitatively reduced and oxidized Ni species on the electrode surface by recording the Ni 2p3/2 signals after cycling the potential in cathodic and anodic regions, respectively. Operando studies demonstrate that a stable electrolyte film forms, allowing the probing of the solid/liquid interface under applied potentials. We attribute this stability to capillary forces within the porous structure of the foam, which enables the monitoring of surface deprotonation under anodic potentials and surface protonation under cathodic potentials. Given that the most common industrial alkaline water electrolyzer electrodes are based on nickel foams similar to the samples measured in this study, the demonstrated method offers a valuable approach for fundamental NAP-XPS examination directly on industrially employed electrodes.
UR - http://www.scopus.com/inward/record.url?scp=105002148563&partnerID=8YFLogxK
U2 - 10.1021/acs.jpclett.4c03362
DO - 10.1021/acs.jpclett.4c03362
M3 - Journal article
C2 - 40178296
AN - SCOPUS:105002148563
SN - 1948-7185
VL - 16
SP - 3597
EP - 3605
JO - Journal of Physical Chemistry Letters
JF - Journal of Physical Chemistry Letters
IS - 14
ER -