Effects of Fe Electrolyte Composition on Ni
(OH )2/NiOOH Structure and Oxygen Evolution Activity
Klaus, S., Cai, Y., Louie, M. W., Trotochaud, L. & Bell, A. T. Effects of Fe Electrolyte Impurities on Ni
Electrochemical characterization, in situ Raman spectroscopy, and quartz crystal microbalance measurements were used to differentiate the effects of structural changes
Significance & impact
We find that
Top Left: Cyclic voltammograms for Ni(OH)2 films deposited on polished Au RDEs in (a) Fe-free and (b) unpurified 1 M KOH after each day of aging. Top Right: In situ Raman spectra of NiOOH after aging in Fe-free and unpurified KOH for six days; the decrease of the 480/560 peak height ratio indicates the presence of a Ni-Fe LDH. Bottom Left: Oxygen evolution activity of electrodeposited NiOOH at 300 mV overpotential and 10 mA·cm−2 geometric current density in 1 M KOH as a function of Fe content (acquired solely from electrolyte impurity uptake).
- Unpurified and Fe-free 1 M KOH solutions were use to study the effects of Fe impurities on the OER over Ni(OH)2/NiOOH films.
- XPS and ICP-OES were used to quantitate Fe uptake within Ni films.
- In situ Raman and quartz crystal microbalance studies revealed structural changes of Fe under conditions of oxygen evolution.