Abstract
Hydrogen (H2) cross-over through a membrane electrolyte is a critical safety issue in
proton exchange membrane
(PEM)
electrolysis.
Permeated H2 tends to be consumed by oxidation or recombination at the anode. In this study, the
contribution of oxidation/recombination to the reduction of the H2 content in
the anode
compartment was quantitatively evaluated by measuring the H2 content during the
electrolysis
operation of a unitized reversible fuel cell stack in which the anode catalyst layer (CL)
contained platinum (Pt). The results of fitting calculation indicated that over 70% of
permeated H2 flux through the membrane was consumed at the anode by oxidation or recombination when
the cathode
pressure was under 10 bars. Therefore, promoting H2 consumption due to the
addition of Pt in either the CL or current collector is critical for safe PEM
electrolysis.
Furthermore, optimization of the electrode structure is also important not only to
increase the Faraday (current) efficiency but also to reduce the H2 content in
the anode.
At the request of the Editors-in-Chief and AIP Publishing this article is being retracted. The article had a high degree of overlap with an article published in the International Journal of Hydrogen Energy. The article is retracted from the scientific record effective 30 June 2017.