Graphite-Conjugated Pyrazines as Molecularly Tunable Heterogeneous Electrocatalysts
Graphite-Conjugated Pyrazines as Molecularly Tunable Heterogeneous Electrocatalysts
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DOI：
10.1021/jacs.5b06737
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发表时间：
2015-09-02
影响因子：
15
通讯作者：
Surendranath, Yogesh
中科院分区：
文献类型：
--
作者：
Fukushima, Tomohiro;Drisdell, Walter;Surendranath, Yogesh
邻苯二胺衍生物与邻醌部分在石墨碳的边缘平面处的缩合生成石墨共轭吡嗪（GCPs），其对于碱性水性电解质中的氧还原电催化是活性的。氧还原的催化速率与活性位点吡嗪单元的亲电性正相关，并且可以通过向苯二胺前体添加吸电子取代基来调节超过70倍。含有吡嗪部分的离散分子类似物在相同条件下不显示高于背景的活性。这种简单的自下而上的方法用于在无处不在的石墨固体上构建分子定义良好的活性位点，使得可调非均相催化剂的合理设计成为可能。
Condensation of ortho-phenylenediamine derivatives with ortho-quinone moieties at edge planes of graphitic carbon generates graphite-conjugated pyrazines (GCPs) that are active for oxygen reduction electro-catalysis in alkaline aqueous electrolyte. Catalytic rates of oxygen reduction are positively correlated with the electrophilicity of the active site pyrazine unit and can be tuned by over 70-fold by appending electron-withdrawing substituents to the phenylenediamine precursors. Discrete molecular analogs containing pyrazine moieties display no activity above background under identical conditions. This simple bottom up method for constructing molecularly well-defined active sites on ubiquitous graphitic solids enables the rational design of tunable heterogeneous catalysts.