Nitrogen‐doped carbon structures have recently been demonstrated as a promising candidate for electrocatalytic CO₂ reduction, while in the meantime the pyridinic and graphitic nitrogen atoms also present high activities for electroreduction of water. Here, an etching strategy that uses hot water steam to preferentially bind to pyridinic and graphitic nitrogen atoms and subsequently etch them in carbon frameworks is reported. As a result, pyrrolic nitrogen atoms with low water affinity are retained after the steam etching, with a much increased level of among all nitrogen species from 22.1 to 55.9%. The steam‐etched nitrogen‐doped carbon catalyst enables excellent electrocatalytic CO₂ reduction performance but low hydrogen evolution reaction activity, suggesting a new approach for tuning electrocatalyst activity.

中文翻译：

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蒸汽选择性腐蚀氮掺杂碳以增强电化学CO2还原

氮掺杂的碳结构最近已被证明是用于电催化还原CO ₂的有前途的候选者，与此同时，吡啶和石墨氮原子也具有很高的水电还原活性。在此，报道了一种蚀刻策略，该策略使用热水蒸汽优先结合吡啶和石墨氮原子，然后在碳骨架中对其进行蚀刻。结果，在蒸汽蚀刻之后保留了低水亲合力的吡咯性氮原子，所有氮物种中的吡咯性氮原子的含量大大提高，从22.1％增至55.9％。蒸汽蚀刻的氮掺杂碳催化剂可实现出色的电催化CO ₂ 还原性能，但析氢反应活性低，表明调节电催化剂活性的新方法。