Environmentally Friendly Non-Metal Solar Photocatalyst C3N4for Efficient Nitrogen Fixation as Foliar Fertilizer
Environmentally Friendly Non-Metal Solar Photocatalyst C3N4for Efficient Nitrogen Fixation as Foliar Fertilizer
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DOI：
10.1002/slct.202001971
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发表时间：
2020-07-15
期刊：
影响因子：
2.1
通讯作者：
Zhao, Weirong
中科院分区：
文献类型：
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作者：
Liu, Yifan;Huang, Xiuying;Zhao, Weirong
基于光催化固氮的半导体有望取代传统的Haber-Bosch工艺合成农业用氮肥。具有太阳光谱响应性的聚碳氮化物(PCN)得到了广泛的应用。为了提高其光催化效率，采用简易的两步焙烧固氮法制备了剥离型氮化碳(C3N4)。扫描电子显微镜/透射电子显微镜结果表明，经二次加热后，剥离的C(3)N(4)光催化剂呈现多孔状。二次焙烧120min的催化剂具有较大的比表面积206m(2)·g(-1)，光催化析氨活性明显提高到PCN的4.20倍。在此基础上，基于第一性原理模拟分析，构建了不同吸附位置的氮吸附体系。结果表明，N(2)分子更有可能以水平方式吸附在二配位氮原子上，其吸附能为-72.59kJ.mol(-1)。为进一步研究N(2)在催化剂上的吸附活性提供了参考。这项工作开发了环境友好的C(3)N(4)催化剂，具有更多的活性中心，与清除剂甘油一起用作潜在的“叶面肥料”系统。
Photocatalytic nitrogen fixation based semiconductors has been expected to replace the traditional Haber-Bosch process to synthesize nitrogen fertilizer for agricultural application. Polymeric carbon nitride (PCN) with the response to solar spectrum has been widely used. In order to improve its photocatalytic efficiency, the exfoliated carbon nitride (C3N4) was prepared with a facile two-step calcining method for nitrogen fixation. SEM/TEM results reveal that with the secondary thermal process, the exfoliated C(3)N(4)photocatalyst shows a porous appearance. The optimal catalyst with secondary calcination for 120 min exhibits large specific surface area of 206 m(2).g(-1)and the photocatalytic activity for ammonium evolution is evidently enhanced to 4.20 times of PCN. Further, nitrogen adsorption systems with different adsorption sites were constructed based on first principles simulation analysis. The result indicated that N(2)molecule was more likely to physically adsorb over the two-coordinated nitrogen atom in the horizontal mode with an adsorption energy of -72.59 kJ.mol(-1). It provided reference for the further study of the N(2)adsorption activity on the catalyst. This work developed environmentally friendly C(3)N(4)catalysts with more active sites to function as prospective "foliar fertilizer" system along with scavenger glycerol.