Metal oxides are used as catalysts in energy and environmental applications. For instance, ruthenium(IV) oxides are oxygen evolution reaction catalysts in water splitting that have been investigated under highly acidic or alkaline conditions. Still, their stability and activity are limited under such harsh conditions. High-valent ruthenium ligand (L) complexes Ru^IV-L and Ru^V-L have been extensively studied for oxygen evolution reaction in non-aqueous environments. The new approach used herein is the combination of two high-valent ruthenium(IV) oxide (Ru^IV) and iron(VI) (Fe^VIO₄²⁻, Fe^VI) that yielded efficient oxygen evolution reaction activity under mild alkaline aqueous conditions, at pH 8.2 and 9.0. The easily available ruthenium(III) ion (Ru^III) reacted with Fe^VI at a molar ratio of 0.25 ([Ru^III]:[Fe^VI]) to produce in situ Ru^IV and unconsumed Fe^VI mixture solution, which had an onset potential around 1.40 V with a shift in onset potential of 260 mV and 150 mV with respect to Ru^III and Fe^VI alone, respectively. The unique mixed solution of Ru^IV-Fe^VI had less resistance to perform the catalytic reaction. Here, we show that combining high-valent ruthenium(IV) oxide and iron(VI) under mild alkaline aqueous conditions exhibits superior performance for oxygen evolution reaction, making it a potential candidate for water splitting reaction.

金属氧化物在能源和环境应用中用作催化剂。例如，钌（IV）氧化物是水分解中的析氧反应催化剂，已在高酸性或碱性条件下进行了研究。尽管如此，它们的稳定性和活性在如此恶劣的条件下仍然受到限制。高价钌配体 (L) 配合物 Ru ^IV -L 和 Ru ^V -L 已被广泛研究用于非水环境中的析氧反应。本文使用的新方法是两种高价氧化钌(IV) (Ru ^IV ) 和铁(VI) (Fe ^VI O ₄ ²⁻ , Fe ^VI ) 的组合，在温和的碱性水条件下产生有效的析氧反应活性，pH 8.2 和 9.0。容易获得的钌(III)离子(Ru ^III )与Fe ^VI以0.25的摩尔比([Ru ^III ]:[Fe ^VI ])反应，原位生成Ru ^IV和未消耗的Fe ^VI混合溶液，其开始发生电势约为 1.40 V，相对于单独的 Ru ^III和 Fe ^VI ，起始电势的变化分别为 260 mV 和 150 mV 。独特的Ru ^IV -Fe ^VI混合溶液对催化反应的阻力较小。在这里，我们证明，在弱碱性水溶液条件下将高价氧化钌（IV）和铁（VI）结合表现出优异的析氧反应性能，使其成为水分解反应的潜在候选者。