Co/ZnO/Nitrogen-Doped Carbon Composite Anode Derived from Metal Organic Frameworks for Lithium Ion Batteries

Abstract

Through high-temperature sintering and carbonization, two Co/ZnO nitrogen-doped porous carbon (NC) composites derived from ZIF-8 and ZIF-67 were manufactured for use as anodes for Li ion batteries: composite-type Co/ZnO-NC and core-shell-type Co@ZnO-NC. X-ray diffraction analysis, scanning electron microscopy, and the Brunauer–Emmett–Teller (BET) method were performed to identify the pore distribution and surface morphology of these composites. The findings of the BET method indicated that the specific surface area of Co/ZnO-NC was 350 m2/g, which was twice that of Co@ZnO-NC. Electrochemical measurements revealed that Co@ZnO-NC and Co/ZnO-NC had specific capacities of over 400 mAh g−1 at a current density 0.2 A g−1 after 50 cycles. After 100 cycles, Co/ZnO-NC exhibited a reversible capacity of 411 mAh g−1 at a current density of 0.2 A g−1 and Co@ZnO-NC had a reversible capacity of 246 mAh g−1 at a current density of 0.2 A g−1. The results indicated that Co/ZnO-NC exhibited superior electrochemical performance to Co@ZnO-NC as a potential anode for use in Li ion batteries.

Influence of ZIF-9 and ZIF-12 structure on the formation of a series of new Co/N-doped porous carbon composites as anode electrodes for high-performance lithium-ion batteries

“…34 Y. Chang et al used Co/ZnO/N-doped ZIF-8 and ZIF-67-derived carbon as an efficient anode material for LIBs with a capacity of 411.0 mA h g −1 at 0.2 A g −1 after 100 cycles. 35 It is noted that the presence and strong interaction of N heteroatom doping and the reduced Co nanoparticles within N-doped porous carbon materials after the carbonization process of initial ZIF precursors can prevent volume expansion and facilitate improving storage capacity, ionic conductivity, cycling stability, and catalytic activity of graphitization process. 36,37 Nevertheless, almost the previous reports are only based on the reagents derived from the family of ZIF-67 and ZIF-8 materials and have yet to elucidate the effect of ZIF structure on the formation of different N-doped porous carbons for improving the electrochemical performance in LIBs.…”