Grupo de Energía y Química Sostenibles, Instituto de Catálisis y Petroleoquímica, CSIC. C/Marie Curie 2, 28049, Madrid, Spain.
Institute of Engineering Thermodynamics/Electrochemical Energy Technology, German Aerospace Center (DLR), Pfaffenwaldring 38-40, 70569, Stuttgart, Germany.
Nat Commun. 2023 Apr 10;14(1):2010. doi: 10.1038/s41467-023-37665-9.
The production of green hydrogen in water electrolyzers is limited by the oxygen evolution reaction (OER). State-of-the-art electrocatalysts are based on Ir. Ru electrocatalysts are a suitable alternative provided their performance is improved. Here we show that low-Ru-content pyrochlores (RMnRuO, R = Y, Tb and Dy) display high activity and durability for the OER in acidic media. YMnRuO is the most stable catalyst, displaying 1.5 V at 10 mA cm for 40 h, or 5000 cycles up to 1.7 V. Computational and experimental results show that the high performance is owed to Ru sites embedded in RuMnO surface layers. A water electrolyser with YMnRuO (with only 0.2 mg cm) reaches 1 A cm at 1.75 V, remaining stable at 200 mA cm for more than 24 h. These results encourage further investigation on Ru catalysts in which a partial replacement of Ru by inexpensive cations can enhance the OER performance.
在水电解槽中生产绿色氢气受到析氧反应（OER）的限制。最先进的电催化剂基于 Ir 和 Ru。如果 Ru 电催化剂的性能得到改善，它们将是一种合适的替代品。在这里，我们表明低 Ru 含量的钙钛矿（RMnRuO，R=Y、Tb 和 Dy）在酸性介质中具有高活性和 OER 耐久性。YMnRuO 是最稳定的催化剂，在 40 小时内 10 mA cm 下显示 1.5 V，或在 1.7 V 下循环 5000 次。计算和实验结果表明，高性能归因于嵌入 RuMnO 表面层中的 Ru 位。使用 YMnRuO（仅 0.2 mg cm）的水电解槽在 1.75 V 时达到 1 A cm，在 200 mA cm 下稳定超过 24 小时。这些结果鼓励进一步研究 Ru 催化剂，其中通过廉价阳离子部分取代 Ru 可以提高 OER 性能。
