Zeolitic Imidazolate Frameworks-Derived Activated Carbon As Electrode Material for Lithium-Sulfur Batteries and Lithium-Ion Batteries

Abstract

Zeolitic imidazolate framework-derived carbon (ZC) material and ZC-sulfur (ZC-S) composite were prepared successfully via a solution method accompanied by facile carbonization and subsequent sulfur impregnation. The ZC and ZC-S materials kept the basic polyhedral morphology of the zeolitic imidazolate framework crystals. Sulfur is homogeneously distributed over and in the ZC porous matrix with a 51.0% sulfur mass content in ZC-S composite. The ZC material exhibits good electrochemical performances in lithium-ion batteries. After 100 cycles at 0.1 A g−1, a reversible discharge capacity of 619 mAh g−1 is still retained, which is benefitted by the micro/mesopores and specific surface area of the synthesized ZC material. When integrated into lithium-sulfur batteries as a cathode, the ZC-S composite exhibits stable discharge capacity of 850 mAh g−1 after 100 cycles at 0.1 C (1 C = 1670 mA g−1). The increased electrochemical properties of the ZC-S electrode compared to the pristine S electrode may be attributed to the advantageous effects of the ZC porous matrix, which serve as a conductive frame promoting electron and lithium ion transportation and provide abundant active sites to increase electrochemical activity and ensnare soluble polysulfides efficiently.