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This content will become publicly available on August 25, 2018

Title: In situ investigation on ultrafast oxygen evolution reactions of water splitting in proton exchange membrane electrolyzer cells

We present that the oxygen evolution reaction (OER) is a half reaction in electrochemical devices, including low-temperature water electrolysis, which is considered as one of the most promising methods to generate hydrogen/oxygen for the storage of energy. It is affected by many factors, and its mechanism is still not completely understood. A proton exchange membrane electrolyzer cell (PEMEC) with optical access to the surface of anode catalyst layer (CL) coupled with a distinguished high-speed and micro-scale visualization system (HMVS) was developed to in situ investigate OERs. It was revealed in real time that OERs only occur on the anode CL adjacent to liquid/gas diffusion layer (LGDL). The CL electrical conductivity plays a crucial role in OERs on CLs. The large in-plane electrical resistance of CLs becomes a threshold of OERs over the entire CL, and causes a lot of catalyst waste in the middle of LGDL pores. Moreover, the oxygen bubble nucleation, growth, and detachment and the effect of current density on those processes were also characterized. Here, this study proposes a new approach for better understanding the mechanisms of OERs and optimizing the design and fabrication of membrane electrode assemblies.
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  1. Univ. of Tennessee, Knoxville, Tullahoma, TN (United States). Department of Mechanical, Aerospace & Biomedical Engineering, UT Space Institute
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Biosciences and Center for Nanophase Materials Science Divisions
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science and Technology Division
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Energy and Transportation Sciences Division
  5. National Renewable Energy Lab. (NREL), Golden, CO (United States). Materials and Chemical Science and Technolog
  6. National Renewable Energy Lab. (NREL), Golden, CO (United States). Mechanical and Thermal Engineering Sciences
Publication Date:
Report Number(s):
Journal ID: ISSN 2050-7488; JMCAET
Grant/Contract Number:
AC36-08GO28308; FE0011585
Accepted Manuscript
Journal Name:
Journal of Materials Chemistry. A
Additional Journal Information:
Journal Volume: 5; Journal Issue: 35; Journal ID: ISSN 2050-7488
Royal Society of Chemistry
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Country of Publication:
United States
36 MATERIALS SCIENCE; 25 ENERGY STORAGE; electrochemical devices; energy storage
OSTI Identifier: