Abstract Carbon nitride nanosheets have shown a great promise for photocatalytic water splitting among numerous photocatalysts due to the versatile advantages. The crucial issues of the weak visible-light absorption and the separation of photo-generated carrier remain a matter of serious concern. Herein, we report a facile calcination-solvothermal-calcination method to prepare nitrogen-deficient carbon nitride nanosheets (DCNS) for the first time, which leads to the simultaneous introduction of nitrogen defects and formation of a fragmented few-layer nanosheet structure. The fragmented few-layer nanosheet structure is known to possess a high specific surface area and abundant interfacial reaction sites, contributing to the rapid consumption of photo-generated carrier. The nitrogen defects are responsible for further boosting the photocatalytic performance by regulating the band structure and optical properties as well as improving the separation efficiency of photo-generated carrier. The optimized DCNS-120 delivers a superior H2 production rate of 5375 μmol·g−1·h−1, considerably higher than that of bulk carbon nitride (164 μmol·g−1·h−1). We anticipate that this work may pave a new pathway to engineering carbon nitride with a matched structure to achieve the desired efficient photocatalytic H2 production under visible-light irradiation.

中文翻译：

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将氮缺陷纳入新型少层氮化碳纳米片以增强光催化制氢

摘要 氮化碳纳米片由于具有多种优点，在众多光催化剂之间显示出光催化分解水的巨大前景。弱可见光吸收和光生载流子分离的关键问题仍然是一个严重关注的问题。在此，我们首次报道了一种简便的煅烧-溶剂热-煅烧方法来制备缺氮氮化碳纳米片（DCNS），该方法导致氮缺陷的同时引入和碎片化几层纳米片结构的形成。已知碎片化的几层纳米片结构具有高比表面积和丰富的界面反应位点，有助于光生载体的快速消耗。氮缺陷通过调节能带结构和光学性质以及提高光生载流子的分离效率来进一步提高光催化性能。优化后的 DCNS-120 可提供 5375 μmol·g-1·h-1 的优异 H2 生成速率，远高于块状氮化碳 (164 μmol·g-1·h-1)。我们预计这项工作可能为设计具有匹配结构的氮化碳铺平新途径，以在可见光照射下实现所需的高效光催化制氢。显着高于块状氮化碳 (164 μmol·g-1·h-1)。我们预计这项工作可能为设计具有匹配结构的氮化碳铺平新途径，以在可见光照射下实现所需的高效光催化制氢。显着高于块状氮化碳 (164 μmol·g-1·h-1)。我们预计这项工作可能为设计具有匹配结构的氮化碳铺平新途径，以在可见光照射下实现所需的高效光催化制氢。