Dajan Fekadu Tsegaye, Wang Yumeng, Sendeku Marshet Getaye, Zhang Yaling, Wu Binglan, Hussain Sabir, Bahri Mohamed, Zhan Xueying, Li Yaping, Li Xiuting, Wang Fengmei
College of Civil and Transportation Engineering, Shenzhen University, Guangdong, 518060, China.
State Key Laboratory of Chemical Resource Engineering, College of Chemistry, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.
Small. 2025 Sep 1:e09147. doi: 10.1002/smll.202509147.
In acid proton exchange membrane water electrolysis (PEMWE), exploring highly active and durable oxygen evolution reaction (OER) electrocatalysts remains a great challenge. Herein, a durable Ru and Ir co-doped spinel cobalt oxide (RuIr-CoO) nanoflower electrocatalyst with low precious metal loading (Ru 2.7 wt% and Ir 0.25 wt%) is designed for acidic water splitting. The RuIr-CoO electrocatalyst exhibits low overpotential of 220 mV to deliver 10 mA cm along with outstanding stability without significant deterioration for 600 h of operation. X-ray absorption spectra analysis indicates an increase in the valence state of the Co site, along with stabilizing the metal-oxygen bond, due to the introduction of both Ru and Ir, thus enhancing catalytic stability. Further, theoretical calculations confirm that the OER reaction process follows the oxygen path mechanism (OPM) with a significantly reduced energy barrier for the rate-determining step than that in the adsorbate evolution mechanism (AEM). Interestingly, the PEM electrolyzers constructed with this anode can deliver a current density of 500 mA cm at 1.67 V with outstanding stability for continuous 500 h operation at 100 mA cm, showing a great promise toward next-generation green hydrogen energy production.
在酸性质子交换膜水电解（PEMWE）中，探索高活性和耐用的析氧反应（OER）电催化剂仍然是一个巨大的挑战。在此，设计了一种低贵金属负载量（Ru 2.7 wt%和Ir 0.25 wt%）的耐用Ru和Ir共掺杂尖晶石钴氧化物（RuIr-CoO）纳米花电催化剂用于酸性水分解。RuIr-CoO电催化剂在提供10 mA cm时表现出220 mV的低过电位，同时具有出色的稳定性，在运行600小时内无明显劣化。X射线吸收光谱分析表明，由于Ru和Ir的引入，Co位点的价态增加，同时稳定了金属-氧键，从而提高了催化稳定性。此外，理论计算证实，OER反应过程遵循氧路径机制（OPM），与吸附质演化机制（AEM）相比，速率决定步骤的能垒显著降低。有趣的是，用这种阳极构建的PEM电解槽在1.67 V下可提供500 mA cm的电流密度，在100 mA cm下连续运行500小时具有出色的稳定性，对下一代绿色氢能生产显示出巨大的前景。
