Water oxidation on a mononuclear manganese heterogeneous catalyst
Water oxidation on a mononuclear manganese heterogeneous catalyst
复制标题
单核锰多相催化剂上的水氧化
DOI：
10.1038/s41929-018-0158-6
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发表时间：
2018-11-01
期刊：
影响因子：
37.8
通讯作者：
Li, Can
中科院分区：
文献类型：
--
作者：
Guan, Jingqi;Duan, Zhiyao;Li, Can
在自然或人工光合作用中，水的氧化是产生分子氧的先决条件。虽然它已被证明，多核活性位点通常是必要的水的氧化，灵感来自天然的氧释放中心CaMn 4 O 5，多核锰簇，单核锰是否也可以有效地催化水的氧化一直是一个长期存在的问题。在此，我们发现，具有嵌入氮掺杂石墨烯（Mn-NG）中的单核锰的非均相催化剂显示出对于化学水氧化的高达214 s-1的转换频率和在10 mA cm-2的电流密度下低至337 mV的电化学过电位。结构表征和密度泛函理论计算表明，Mn-NG的高活性可以归因于单核锰离子与嵌入石墨烯基质中的四个氮原子的配位。
Water oxidation is the prerequisite for dioxygen evolution in natural or artificial photosynthesis. Although it has been demonstrated that multinuclear active sites are commonly necessary for water oxidation, as inspired by the natural oxygen-evolving centre CaMn4O5, a multinuclear manganese cluster, whether mononuclear manganese can also efficiently catalyse water oxidation has been a long-standing question. Herein, we found that a heterogeneous catalyst with mononuclear manganese embedded in nitrogen-doped graphene (Mn-NG) shows a turnover frequency as high as 214 s−1for chemical water oxidation and an electrochemical overpotential as low as 337 mV at a current density of 10 mA cm−2. Structural characterization and density functional theory calculations reveal that the high activity of Mn-NG can be attributed to the mononuclear manganese ion coordinated with four nitrogen atoms embedded in the graphene matrix.