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DOE OSTI · 3407884

Activity Convergence between Continuous- and Pulsed-Deposition NiFe Hydroxide Anodes in Liquid Alkaline Electrolyzers

Twight, Liam [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Osmieri, Luigi [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Leonard, Daniel P. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000264959582)
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Abstract

Improving the activity of anodes for the alkaline oxygen evolution reaction (OER) is of interest because of the importance of the reaction in electrochemical technology. There is an abundance of studies which confirm that NiFe hydroxide, often prepared by electrodeposition, is the most active catalyst for the alkaline OER. This relatively high level of confidence in the optimal OER catalyst chemistry suggests that exploration of methods which improve on features besides the chemistry of the films, such as their microstructure, could access new heights of activity. In this study, the possible benefits of pulsed current deposition relative to the conventional continuous current approach to the deposition of NiFe hydroxides were investigated. Pulsed deposition densified the film surfaces by preventing metal ion depletion at the electrode surface during film formation. The Fe content, redox reversibility, and OER activity were higher for the pulsed deposition films relative to their continuous deposition counterparts. Though pulsed deposition imparted a higher OER performance of the films compared to continuous deposition at the three-electrode level, this improved performance was not retained during electrolyzer operation. Rather, a convergence of the cell performance is seen irrespective of the deposition approach. This phenomenon was attributed to the way electrolyzer conditionsrelatively high temperature, base concentration, and current densitycan drive alternate mechanisms for observed performance.

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08 HYDROGEN36 MATERIALS SCIENCEOER catalysishydrogen generationliquid alkaline water electrolyzernickel−iron hydroxidepulsed deposition

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Twight, Liam [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Osmieri, Luigi [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Leonard, Daniel P. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000264959582). 2026-07-21. Activity Convergence between Continuous- and Pulsed-Deposition NiFe Hydroxide Anodes in Liquid Alkaline Electrolyzers. https://doi.org/10.1021/acsami.6c05938

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