Abstract
Improving utilization, performance, and stability of low iridium (Ir)-loaded anodes is a key goal to enable widespread adoption of polymer electrolyte membrane water electrolysis (PEMWE) for clean hydrogen production. A potential limitation is high ionic or electronic resistance of the anode catalyst layer, which leads to poor catalyst utilization, increased voltage losses, and high local overpotentials that can accelerate degradation. While catalyst layer resistance is relatively well-understood in fuel cells and other porous electrode systems, characterization of these effects is not as well established in PEMWE research. Here we present in-situ methods for measuring catalyst layer resistance in electrolysis cells using a non-faradaic H2/H2O condition as well as methods for calculating the associated voltage losses. These methods are applied to anode catalyst layers based on IrO2 nanoparticles as well as dispersed nano-structured thin film (NSTF) Ir catalysts. Trends with anode catalyst loading and interactions between the porous transport layer and catalyst layer are investigated for IrO2 anodes. Post-mortem microscopic analysis of durability-tested anodes is also presented, showing uneven degradation of the catalyst layer caused by catalyst layer resistance.
| Original language | English |
|---|---|
| Article number | 084512 |
| Journal | Journal of the Electrochemical Society |
| Volume | 170 |
| Issue number | 8 |
| DOIs | |
| State | Published - 2023 |
Funding
This work was authored by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36–08GO28308. Funding provided by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office through award DE-EE0009237 and the H2NEW consortium. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. The authors thank Timothy Van Cleve, KC Neyerlin, Prantik Saha, Bryan Pivovar, Tobias Schuler, Jacob Wrubel, Robin Rice, and Megan Holtz for useful conversations, and Ellis Klein and Christian Milleville for testing and facility support. The Talos F200X was provided by US DOE, Office of Nuclear Energy, Fuel Cycle R&D Program and the Nuclear Science User Facilities. This work was authored by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided by U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office through award DE-EE0009237 and the H2NEW consortium. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. The authors thank Timothy Van Cleve, KC Neyerlin, Prantik Saha, Bryan Pivovar, Tobias Schuler, Jacob Wrubel, Robin Rice, and Megan Holtz for useful conversations, and Ellis Klein and Christian Milleville for testing and facility support. The Talos F200X was provided by US DOE, Office of Nuclear Energy, Fuel Cycle R&D Program and the Nuclear Science User Facilities.
| Funders | Funder number |
|---|---|
| U.S. Government | |
| U.S. Department of Energy | DE-AC36–08GO28308 |
| Hydrogen and Fuel Cell Technologies Office | DE-EE0009237 |
