Journal
NANO ENERGY
Volume 41, Issue -, Pages 765-771Publisher
ELSEVIER SCIENCE BV
DOI: 10.1016/j.nanoen.2017.07.053
Keywords
Hydrogen oxidation reaction; Alkaline electrocatalysis; Alkaline membrane fuel cells; Electrochemical double-layer structure; Quasi-specific adsorption; X-ray absorption spectroscopy
Categories
Funding
- Army Research Office under the Single Investigator grant
- ARPA-E [DE-AR0000688]
- U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences [DE-SC0012704, DE-AC02-76SF00515]
Ask authors/readers for more resources
Enhancing the sluggish kinetics of electrochemical hydrogen-oxidation reaction in high pH environments is of crucial importance considering its applications in alkaline-membrane fuel cells (AMFC) and regenerative hydrogen electrodes for energy storage. Alkaline H-2-oxidation to form water involves reaction between H-adsorbed intermediates and hydroxide anions wherein the nature/source of the latter plays a crucial role. Here, we take a systematic approach to understand why H-2-oxidation kinetics is slower in alkaline media compared to acid. While recently reported models focus on surface-adsorbate bond strength optimization, we herein show that the alkaline H-2-oxidation mechanism is fundamentally different due to a complex interplay between electrocatalysis and electrochemical double-layer structure. A heretofore unknown modern rendition of the double-layer structure is proposed wherein specifically adsorbed (M-OHad) and quasi-specifically adsorbed (M-(Had/updOHq-ad)-O-center dot center dot center dot) reactive hydroxide-species localized in the compact part of the electrochemical double-layer is shown to define H-2-oxidation kinetics on monometallic and bimetallic catalyst surfaces at high pH.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available