Abstract
Clean hydrogen production requires large-scale deployment of water-electrolysis technologies, particularly proton-exchange-membrane water electrolyzers (PEMWEs). However, as iridium-based electrocatalysts remain the only practical option for PEMWEs, their low abundance will become a bottleneck for a sustainable hydrogen economy. Herein, we propose high-performing and durable ionomer-free porous transport electrodes (PTEs) with facile recycling features enabling Ir thrifting and reclamation. The ionomer-free porous transport electrodes offer a practical pathway to investigate the role of ionomer in the catalyst layer and, from microelectrode measurements, point to an ionomer poisoning effect for the oxygen evolution reaction. The ionomer-free porous transport electrodes demonstrate a voltage reduction of > 600 mV compared to conventional ionomer-coated porous transport electrodes at 1.8 A cm−2 and <0.1 mgIr cm−2, and a voltage degradation of 29 mV at average rate of 0.58 mV per 1000-cycles after 50k cycles of accelerated-stress tests at 4 A cm−2. Moreover, the ionomer-free feature enables facile recycling of multiple components of PEMWEs, which is critical to a circular clean hydrogen economy.
| Original language | English |
|---|---|
| Article number | 4592 |
| Journal | Nature Communications |
| Volume | 14 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2023 |
Funding
The authors acknowledge the Department of Energy–Office of Energy Efficiency and Renewable Energy–Hydrogen and Fuel Cell Technologies Office (DOE-EERE-FCTO) and the H2 from the Next-generation of Electrolyzers of Water (H2NEW) consortium for funding under Contract Number DE-AC02-05CH11231. This research used resources of the Advanced Light Source (ALS), a DOE Office of Science User Facility under contract no. DEAC02-05CH11231. We are grateful to Dr. Dula Parkinson for helping with micro-tomography measurement at Beamline 8.3.2 of ALS. All opinions expressed in this paper are the author’s and do not necessarily reflect the policies and views of DOE. N.D., J.K.L., A.Z.W., X.P. has patent Treatment of A Porous Transport Layer for Use in An Electrolyzer pending to The Regents of The University of California (U.S. Patent Application No. 18/332,886). The authors acknowledge the Department of Energy–Office of Energy Efficiency and Renewable Energy–Hydrogen and Fuel Cell Technologies Office (DOE-EERE-FCTO) and the H2 from the Next-generation of Electrolyzers of Water (H2NEW) consortium for funding under Contract Number DE-AC02-05CH11231. This research used resources of the Advanced Light Source (ALS), a DOE Office of Science User Facility under contract no. DEAC02-05CH11231. We are grateful to Dr. Dula Parkinson for helping with micro-tomography measurement at Beamline 8.3.2 of ALS. All opinions expressed in this paper are the author’s and do not necessarily reflect the policies and views of DOE. N.D., J.K.L., A.Z.W., X.P. has patent Treatment of A Porous Transport Layer for Use in An Electrolyzer pending to The Regents of The University of California (U.S. Patent Application No. 18/332,886).
