Two-Dimensional Covalent Organic Framework with Synergistic Active Centers for Efficient Electrochemical Sodium Storage

作者：Zhang, Meng; Tong, Yifan; Sun, Zhaopeng; Wang, Jiawen; Lin, Yilin; Kang, Fangyuan; Zhang, Qichun^*; Huang, Weiwei^*

来源：Chemistry of Materials, 2023.

DOI：10.1021/acs.chemmater.3c00983

• CONJUGATED POLYMER
• ION BATTERIES
• FAST-CHARGE
• CATHODE

Benefitingfrom the adjustable molecule structures, abundant functionalunits, large specific surface areas, and ordered pores, covalent organicframeworks (COFs) are highly desirable for electrochemical energystorage. Herein, a two-dimensional COF (denoted as HHTP-TABQ) witha fully & pi;-conjugated framework and C N and C Odual-active sites has been synthesized and applied as the anode inorganic rechargeable sodium-ion batteries (SIBs). During the sodium-storageprocess, it delivered remarkable rate capability, satisfactory ultra-longcycle stability (84.5% capacity retention ratio after 1000 cyclesat 5000 mA g(-1)), and facile charge exchange kinetics(2.49 x 10(-7) cm(2) s(-1)), which is superior among most reported COF-based electrodes. Furthermore,the sodiation mechanism was investigated by density functional theorycalculations and ex situ characterizations, which confirms that theelectrochemical reaction is dominated by the synergistic reactionof C N and C O groups. These results suggest that COFswith stable & pi;-conjugated structures, insoluble characteristics,and abundant active sites would have great potential for practicalapplications in rechargeable SIBs.

• 单位
  燕山大学