Potassium Ion Assisted Regeneration of Active Cyano Groups in Carbon Nitride Nanoribbons: Visible Light Driven Photocatalytic Nitrogen Reduction
Potassium Ion Assisted Regeneration of Active Cyano Groups in Carbon Nitride Nanoribbons: Visible Light Driven Photocatalytic Nitrogen Reduction
复制标题
钾离子辅助氮化碳纳米带中活性氰基的再生：可见光驱动的光催化氮还原
DOI：
10.1002/anie.201908640
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发表时间：
2019-10-01
影响因子：
16.6
通讯作者：
Zhao, Huijun
中科院分区：
文献类型：
--
作者：
Wang, Weikang;Zhang, Haimin;Zhao, Huijun
作为一种无金属氮还原反应（NRR）光催化剂，g-C3 N4可通过低成本的规模化合成获得。重要的是，它可以很容易地官能化，以提高光催化活性。然而，使用g-C3 N4为基础的光催化剂的NRR一直受到质疑，因为难以捉摸的机制和参与的N缺陷。本工作报道了用氰基和插层K+（mCNN）修饰的g-C3 N4光催化剂的合成，其具有扩展的可见光捕获能力和上级光催化NRR活性（NH3产率：3.42 mmol g（-1）h（-1））。实验和理论研究表明，mCNN中相当于N的-C可以在插入的K+的帮助下通过类似于Mars货车Krevelen过程的途径再生。结果表明，氰基的再生不仅提高了光催化活性，维持了催化循环，而且稳定了光催化剂。
As a metal-free nitrogen reduction reaction (NRR) photocatalyst, g-C3N4 is available from a scalable synthesis at low cost. Importantly, it can be readily functionalized to enhance photocatalytic activities. However, the use of g-C3N4-based photocatalysts for the NRR has been questioned because of the elusive mechanism and the involvement of N defects. This work reports the synthesis of a g-C3N4 photocatalyst modified with cyano groups and intercalated K+ (mCNN), possessing extended visible-light harvesting capacity and superior photocatalytic NRR activity (NH3 yield: 3.42 mmol g(-1) h(-1)). Experimental and theoretical studies suggest that the -C equivalent to N in mCNN can be regenerated through a pathway analogous to Mars van Krevelen process with the aid of the intercalated K+. The results confirm that the regeneration of the cyano group not only enhances photocatalytic activity and sustains the catalytic cycle, but also stabilizes the photocatalyst.