Thrifting iridium for hydrogen

Pendergast, Andrew D. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)]; Boettcher, Shannon W. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States); Univ. of Oregon, Eugene, OR (United States)]

doi:10.1126/science.adv4929

DOE OSTI · 2538436

Thrifting iridium for hydrogen

Pendergast, Andrew D. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)]·Boettcher, Shannon W. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States); Univ. of Oregon, Eugene, OR (United States)]

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Abstract

Using renewable electricity to produce hydrogen fuel reduces reliance on fossil fuels. Proton exchange membrane water electrolyzers (PEMWEs) are the highest-performing commercialized technology. These devices split water into oxygen gas and hydrogen ions (protons) at the anode. The protons then migrate through an ion-conducting polymer membrane (ionomer) to be reduced to hydrogen gas at the cathode. Further, the anode reaction’s harsh environment requires the use of precious-metal catalysts, such as iridium oxide (IrO x ). Given the expense and scarcity, the design of electrodes that minimize the use of precious metals without compromising the requisite stability and activity is desired for large-scale hydrogen production. On page 791 of this issue, Shi et al. report that anchoring IrO x catalysts onto porous cerium-oxide (CeO x ) supports maintains performance even with much reduced precious metal use.

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BibTeX RIS

Pendergast, Andrew D. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)], Boettcher, Shannon W. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States); Univ. of Oregon, Eugene, OR (United States)]. 2025-02-14. Thrifting iridium for hydrogen. https://doi.org/10.1126/science.adv4929

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