Assembly of GO Nanosheets-Coated Zeolitic Imidazolate Framework-67 Nanocubes via Electrospinning and Their Derivatives for Enhanced Lithium-Ion Storage Performance

摘要

Zeolitic imidazolate framework-67 (ZIF-67)-derived Co3O4/N-doped porous carbon hybrids have drawn great attention as anode materials for lithium-ion batteries (LIBs) because of their unique advantages. Herein, based on the electrospinning-assisted assembly method, two strategies are used to further enhance the stability and capacity of the anodes; one is increasing the crystallinity of ZIF-67 nanocubes (NCs) to raise the specific surface area and porosity, and the other is coating GO nanosheets on the surfaces of ZIF-67 (ZIF-67@GO) to improve the conductivity and capacity and buffer the sintering during the cycling process. After electrospinning of ZIF-67@GO NCs followed by a two-step thermal treatment, hollow Co3O4 nanoparticles encapsulated N-doped porous carbon nanofibers with high graphitization degree are constructed (ES-CNCo3O4@rGO). When applied as the anode for LIBs, the ES-CNCo3O4@rGO electrode exhibits excellent rate capability and high specific capacity as well as stable cycling performance (1315 mAh g(-1) after 100 cycles at 0.1 A g(-1) and 1234 mAh g(-1) after 500 cycles at 1 A g(-1)).