Leiden Institute of Chemistry, Leiden University , P.O. Box 9502, 2300 RA, Leiden, The Netherlands.
J Am Chem Soc. 2014 Jul 23;136(29):10432-9. doi: 10.1021/ja504460w. Epub 2014 Jul 10.
We present a systematic electrochemical and spectroelectrochemical study of the catalytic activity for water oxidation of an iridium-N-dimethylimidazolin-2-ylidene (Ir-NHC-Me2) complex adsorbed on a polycrystalline gold electrode. The work aims to understand the effect of the electrolyte properties (anions and acidity) on the activity of the molecular catalyst and check its stability toward decomposition. Our results show that the iridium complex displays a very strong dependence on the electrolyte properties such that large enhancements in catalytic activity may be obtained by adequately choosing pH and anions in the electrolyte. The stability of the adsorbed compound was investigated in situ by Surface Enhanced Raman Spectroscopy and Online Electrochemical Mass Spectrometry showing that the catalyst exhibits good stability under anodic conditions, with no observable evidence for the decomposition to iridium oxide.
我们对吸附在多晶金电极上的铱-N-二甲基咪唑啉-2-亚基（Ir-NHC-Me2）配合物的水氧化催化活性进行了系统的电化学和光谱电化学研究。这项工作旨在了解电解质性质（阴离子和酸度）对分子催化剂活性的影响，并检查其对分解的稳定性。我们的结果表明，铱配合物对电解质性质有很强的依赖性，因此通过适当选择 pH 值和电解质中的阴离子，可以获得很大的催化活性增强。通过表面增强拉曼光谱和在线电化学质谱原位研究了吸附化合物的稳定性，结果表明催化剂在阳极条件下具有良好的稳定性，没有观察到催化剂分解为氧化铱的迹象。
