Activity Convergence between Continuous- and Pulsed-Deposition NiFe Hydroxide Anodes in Liquid Alkaline Electrolyzers
Liam Twight1, Luigi Osmieri1, Daniel P Leonard1
1Materials Synthesis and Integrated Devices Group (MPA-11), Los Alamos National Laboratory, Los Alamos, New Mexico87545-1663, United States.
ACS Applied Materials & Interfaces
|August 5, 2026
Summary
Pulsed deposition enhances nickel-iron hydroxide (NiFe) anode activity for alkaline oxygen evolution reaction (OER) by improving microstructure. However, this benefit diminishes under electrolyzer conditions, suggesting alternative performance mechanisms.
Area of Science:
- Electrochemistry
- Materials Science
Background:
- The alkaline oxygen evolution reaction (OER) is crucial for electrochemical technologies.
- Nickel-iron hydroxide (NiFe) is a highly active catalyst for alkaline OER, often prepared via electrodeposition.
Purpose of the Study:
- Investigate the impact of pulsed current deposition versus continuous current deposition on NiFe hydroxide microstructure and OER activity.
- Explore methods to enhance NiFe hydroxide catalyst performance beyond chemical composition.
Main Methods:
- Electrodeposition of NiFe hydroxide films using both pulsed and continuous current methods.
- Characterization of film microstructure, iron content, and redox reversibility.
- Evaluation of OER activity using three-electrode and electrolyzer setups.
Main Results:
- Pulsed deposition resulted in denser NiFe hydroxide films with higher Fe content and improved redox reversibility.
- NiFe films prepared by pulsed deposition exhibited superior OER activity at the three-electrode level.
- Performance of pulsed and continuous deposition films converged under electrolyzer conditions.
Conclusions:
- Pulsed current deposition offers microstructural advantages for NiFe hydroxide OER catalysts.
- Electrolyzer operating conditions can mask initial deposition benefits by promoting alternative reaction mechanisms.
- Further research is needed to optimize catalysts for real-world electrolyzer performance.
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