C
2N的结构与石墨烯相似,主要由sp
2杂化的碳原子组成。但与石墨烯不同的是,C
2N是一种平面存在周期性小孔,孔的边界由氮原子组成,导致电子在氮原子上富集的材料。由于C2N具有表面积高、结晶度良好和离子传输快速等优点,在催化、纳米电子传感器、气体存储和电池等领域有着广泛的应用。C
2N材料是当前的一个研究热点之一,负载的过渡金属或贵金属元素作为可能的催化活性位点受到了广泛的关注。最近几年在合成和应用C
2N材料方面已经取得了很大进展,然而对材料中金属纳米颗粒的几何结构、电子性质及其形成机理仍不清楚,此外对催化反应的微观机理缺乏深入的认识。本文综述了C
2N体系的几何形状和稳定性,电子结构分析,选择合适的理论计算方法可探究在C
2N上锚定金属原子体系的催化性能,为我们提供了结构和性能等方面的重要信息,从而为设计出性能更好的催化剂提供借鉴与指导意义。
The structure of C
2N is similar to graphene, mainly composed of sp
2 hybridized carbon atoms. But unlike graphene, there are periodic pores in the C
2N plane, and the boundary of the pores is composed of nitrogen atoms, resulting in a material where electrons are enriched in nitrogen atoms. Because C
2N has the advantages of high surface area, good crystallinity and fast ion transmission, it has a wide range of energy and environmental applications in the fields of catalysis, nanoelectronic sensors, gas storage, and batteries. C
2N materials are currently a research hotspot, and supported transition metals or metal-free elements have received extensive attention as possible catalytically active sites. In recent years, great progress has been made in the synthesis and application of C
2N materials. However, the geometric structure, electronic properties and formation mechanism of metal nanoparticles in the materials are still unclear. In addition, there is a lack of in-depth understanding of the microscopic mechanism of catalytic reactions. This article reviews the geometry and stability of the C
2N system, analysis of the electronic structure, and selects appropriate theoretical calculation methods to explore the catalytic performance of the metal atom system anchored to C
2N. It provides us with important information on the structure and performance. It provides reference and guidance for the design of better performance catalysts.
The structure of C2N is similar to graphene, mainly composed of sp2 hybridized carbon atoms. But unlike graphene, there are periodic pores in the C2N plane, and the boundary of the pores is composed of nitrogen atoms, resulting in a material where electrons are enriched in nitrogen atoms. Because C2N has the advantages of high surface area, good crystallinity and fast ion transmission, it has a wide range of energy and environmental applications in the fields of catalysis, nanoelectronic sensors, gas storage, and batteries. C2N materials are currently a research hotspot, and supported transition metals or metal-free elements have received extensive attention as possible catalytically active sites. In recent years, great progress has been made in the synthesis and application of C2N materials. However, the geometric structure, electronic properties and formation mechanism of metal nanoparticles in the materials are still unclear. In addition, there is a lack of in-depth understanding of the microscopic mechanism of catalytic reactions. This article reviews the geometry and stability of the C2N system, analysis of the electronic structure, and selects appropriate theoretical calculation methods to explore the catalytic performance of the metal atom system anchored to C2N. It provides us with important information on the structure and performance. It provides reference and guidance for the design of better performance catalysts.
文章中首先模拟了单个TMx+离子(Co2+,Ni2+和Cu2+)在小的C2N模型簇上的沉积。这种C2N-TMx+系统的形成非常稳定,这是因为TM离子与两个键长为1.99~2.18 Å的N原子之间的牢固结合。计算出的锚定在C2N上的Co2+,Ni2+和Cu2+的结合能均大于14 eV (表1),表明存在很强的耦合。发现沿着一个空位圆从一个吸附位置到相邻一个吸附位置的扩散势垒仅为0.07 eV,这表明离子容易沿着空位圆漂移。但是,从一个孔位到相邻孔位的扩散势垒高达3.91 eV,表明TMx+与氮之间的强相互作用阻止了TMx+的聚集。
Computed binding energies of TMx+ on C2N, adsorption energies of the HCOOH molecule on C2N-TMx+, charges extracted from C2N to TMx+ (C2N→TMx+) in the hybrid systems, and charges extracted from HCOOH to C2N-TMx+ in the adsorption configuratio
孔程程,黄华荃. 二维多孔材料C2N理论研究综述A Summary of C2N Theoretical Research on Two-Dimensional Porous Materials[J]. 材料化学前沿, 2021, 09(03): 71-79. https://doi.org/10.12677/AMC.2021.93009
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