クリーン水素のイリジウム問題を迅速に解決(Clean hydrogen’s iridium problem? Solved in an afternoon)

2025-08-19 ノースウェスタン大学

ノースウェスタン大学の研究チームは、水の電気分解で不可欠とされてきた高価なイリジウム触媒に代わる新材料を発見した。研究では、数百万のナノ粒子を同時に合成・評価できる「メガライブラリ」を用い、ルテニウム・コバルト・マンガン・クロムを組み合わせた数千万の候補を短時間で探索。その結果、Ru₅₂Co₃₃Mn₉Cr₆酸化物が、イリジウムを上回る触媒活性と優れた安定性を示し、酸性条件下で1000時間以上の耐久試験にも耐えることが判明した。コストはイリジウムの約1/16にとどまり、実用化すればクリーン水素の経済性を大幅に改善できる。本成果は、触媒開発のみならず、AIや機械学習と組み合わせることで電池や医療、光学分野にも応用可能であり、持続可能なエネルギー社会実現に向けた大きな前進となる。

<関連情報>

メガライブラリを活用した酸素進化反応触媒の発見加速 Accelerating the Pace of Oxygen Evolution Reaction Catalyst Discovery through Megalibraries

Jin Huang,Zhe Wang,Jiashun Liang,Xiao-Yan Li,Jacob Pietryga,Zihao Ye,Peter T. Smith,Alp Kulaksizoglu,Connor R. McCormick,Jaerim Kim,Bosi Peng,Zeyan Liu,Ke Xie,Steven B. Torrisi,Joseph H. Montoya,Gang Wu,Edward H. Sargent,and Chad A. Mirkin
Journal of the American Chemical Society  Published: August 19, 2025
DOI:https://doi.org/10.1021/jacs.5c08326

Abstract

クリーン水素のイリジウム問題を迅速に解決(Clean hydrogen’s iridium problem? Solved in an afternoon)

Iridium (Ir) catalysts are essential for the acidic oxygen evolution reaction (OER) in proton-exchange membrane water electrolyzers (PEMWEs), but their high cost, scarcity, and geographical concentration limit large-scale adoption. In addition, the discovery of non-Ir alternatives is slow due to the vast design space possible. Here, a “megalibrary” is used to explore the catalytic activity of ∼156 million distinct nanostructures comprised of Ru, Co, Mn, and Cr to find alternatives to Ir catalysts for OER. Over 40 RuCoMnCr oxides, ranging from low to high activity, were selected, scaled to milligram levels, and studied for their catalytic performance. The activities measured within the megalibrary closely correlated (r = 0.84) with those of the macroscopic samples. In a PEMWE, the most active catalyst, Ru52Co33Mn9Cr6 oxide, demonstrated a voltage of 1.58 V at 1 A/cm2 and 1.77 V at 3 A/cm2. At 1 A/cm2, it operated continuously for over 1000 h with an average voltage increase rate of 57 μV/h. This study establishes a roadmap to accelerate catalyst discovery for energy conversion, and the platform is a route to large data sets that will facilitate the development of AI and machine learning algorithms that can identify key catalyst design features.

0500化学一般
ad
ad
Follow
ad
タイトルとURLをコピーしました