9月27日，我院黄俊杰教授课题组在锂离子电池有机负极材料领域取得了重要进展，在ACS Applied Materials & Interfaces期刊上发表了“Superlithiation Performance of Covalent Triazine Frameworks as Anode in Lithium Ion Batteries”(DOI: 10.1021/acsami.1c14838)的研究论文。该研究探索了以三嗪环为共价链接单元的共价三嗪有机框架化合物（CTFs）负极材料的电化学储锂性能以及合成温度对电化学性能的影响，为CTFs-1材料的制备及储能研究提供了有效借鉴。

图1 CTFs-1-400材料的超锂化存储机制

该研究通过设计两步合成法来规避传统离子热合成法的缺陷，合成的材料不仅继承了传统导电聚合物优异的电导率和稳定的结构优势，而且具有高度有序的层状微孔结构。得益于其独特的二维多孔结构，在400℃下合成的CTFs-1-400材料具有最佳的电化学储锂性能。在0.1 A g^-1的电流密度下循环100圈后依旧表现出了1626 mAh g^-1的可逆比容量，这不同于传统的石墨材料芳香六元环的LiC₆的储锂机制，而是实现了接近于Li₆C₆的超高储锂比容量，这种储锂机制被称为“超锂化”机制。随着测试温度的升高，电化学动力学得到了进一步的提升，因此在45ºC的测试环境下该材料的可逆储锂比容量会进一步提升到1913 mAh g^-1，实现了商业化石墨负极材料储锂比容量（370 mAh g^-1）的5倍之多。

《ACS Applied Materials & Interfaces》（IF = 9.229）为美国化学会ACS旗下电化学储能领域的权威期刊，中科院期刊分区为一区。

Abstract

Organics with the merit of renewability have been viewed as the promisingalternative of inorganic electrode materials in lithium-ion batteries, but most of them displayinferior performance due to the sluggish ion/electron diffusion and the potential dissolution inaprotic electrolytes. Here, covalent triazine frameworks (CTFs-1), full of vertical pores andlayered spaces for Li⁺ transfer, have beensynthesized with p-dicyanobenzene as the monomerby a facile two-step method including a prepolymerization with CF₃SO₃H as the catalyst and deep polymerization in molten ZnCl₂. CTFs-1-400, obtained at the deep polymerization temperature of 400 °C, exhibits the superlithiation property with the specific capacities of 1626 mA h g⁻¹ at 25 °C and 1913 mA h g⁻¹ at 45 °C at 100 mA g⁻¹, indicating the formation of Li₆C₆/Li₆C₃N₃ in the reduction process. Electrochemical analysis and density functional theory calculation indicate that the ultrahigh capacity is mainly contributed by the capacitance of micropores and the redox capacity of benzene and triazine rings. Moreover, CTFs-1-400 displays the specific capacity of 740 mA h g^-1 for 1000 cycles at 1 A g⁻¹ with almost nocapacity fading.  

论文地址：https://pubs.acs.org/doi/10.1021/acsami.1c14838