Department of Chemistry, Seoul National University, 1 Gwanak-ro, Seoul 151-747 (Republic of Korea).
Angew Chem Int Ed Engl. 2015 Jun 22;54(26):7626-30. doi: 10.1002/anie.201500410. Epub 2015 May 12.
The nature of hydrated protons is an important topic in the fundamental study of electrode processes in acidic environment. For example, it is not yet clear whether hydrated protons are formed in the solution or on the electrode surface in the hydrogen evolution reaction on a Pt electrode. Using mass spectrometry and infrared spectroscopy, we show that hydrogen atoms are converted into hydrated protons directly on a Pt(111) surface coadsorbed with hydrogen and water in ultrahigh vacuum. The hydrated protons are preferentially stabilized as multiply hydrated species (H5 O2 (+) and H7 O3 (+) ) rather than as hydronium (H3 O(+) ) ions. These surface-bound hydrated protons may play an important role in the interconversion between adsorbed hydrogen atoms and solvated protons in solution.
水合质子的性质是酸性环境中电极过程基础研究的一个重要课题。例如，在 Pt 电极上的析氢反应中，水合质子是在溶液中形成还是在电极表面形成尚不清楚。我们使用质谱和红外光谱表明，在超高真空条件下，在 Pt(111)表面共吸附氢和水时，氢原子直接转化为水合质子。这些水合质子优先稳定为多水合物种（H5 O2 (+) 和 H7 O3 (+) ）而不是质子化氢离子（H3 O(+) ）。这些表面结合的水合质子可能在吸附氢原子和溶液中溶剂化质子之间的相互转化中起重要作用。
