Self-assembly of carbon nanotubes on a hollow carbon polyhedron to enhance the potassium storage cycling stability of metal organic framework-derived metallic selenide anodes

• Published in: Journal of colloid and interface science 2021-11, Vol.601, p.60-69
• Main Authors: Wang, Lin, Jiang, Qingqing, Yang, Kun, Sun, Yifan, Zhou, Tengfei, Huang, Zhengxi, Yang, Hai-Jian, Hu, Juncheng
• Format: Article
• Language: English
• Subjects: CNTs; Cobalt selenide; Long-term cycling stability; Potassium-ion batteries; ZIF-8@ZIF-67
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2021.05.064

Herein, MOFs derived hierarchical carbon structure, self-assembly of CNTs on hollow carbon polyhedron has been used as carbon matrix to disperse and stabilize the metal selenides. When CNTs and 3D porous carbon matrix are combined with metal selenides, synergistic effects are given which shows noticed cycle stability. [Display omitted] Potassium-ion batteries (PIBs) is increasingly studied because of their suitable redox potential and high natural abundance. However, potential anode materials with long-term cycling stability are still in high demand because of the large radius of K+. Herein, an MOF-derived hierarchical carbon structure and the self-assembly of CNTs on hollow carbon polyhedrons are used as carbon matrices to disperse and stabilize metal selenides(Co-Se@CNNCP). When the hybrid is utilized in PIBs, it displays a specific capacity of 410 mA h g−1 at 0.1 A g−1 after 80 cycles and 253 mA h g−1 at 0.5 A g−1 after 200 cycles with a capacity retention of 100%, while the metal selenides dispersed on hollow carbon polyhedrons without CNTs (Zn-Co-Se@NCP) lose 86% of their capacity after 200 cycles. The superior cycling stability of the hybrid is mainly attributed to the large amounts of CNTs suppressing the agglomeration of the metal selenide nanoparticles on the surface, and the hollow carbon polyhedrons cause a high structural integrity during the repreated K+ insertion and extraction process. This work offers a feasible route to design a hierarchical carbon matrix for use as the anode materials of PIBs with long-term cycling stability.