Kaiyi Qin1
Northeastern University1
The lithium storage performance and structural stability of anode materials have a significant influence on the capacity performance and cycling stability of lithium-ion batteries. Despite the cost, conductivity, non-toxicity, and non-polluting advantages of graphitic carbon materials, their cycle stability is compromised by volume changes during lithium storage. Additionally, the theoretical capacity of 372 mAh/g is no longer sufficient to meet the growing demand for high-capacity LIBs. Metal-organic frameworks (MOFs) and their derivatives have emerged as promising anode materials for LIBs due to their tunable structure, high surface area, and high porosity. In this study, we successfully synthesized Fe, N co-doped carbon materials (Fe-N-C) with exceptional properties by calcination and co-doping Fe and N elements into a ZIF-8 precursor. Scanning electron microscopy (SEM) results revealed that the morphology of the synthesized samples was identical to that of ZIF-8. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses confirmed the successful co-doping of Fe and N into the carbon material. The porous structure provided a buffer for volume changes and improved cycling performance. After 300 cycles at a current density of 500 mA/g, the Fe-N-C anode exhibited charge and discharge specific capacities of 538 mAh/g and 543 mAh/g, respectively. The co-doping of Fe and N enhanced the conductivity and rate performance of Fe-N-C, resulting in excellent cycling stability. This study demonstrates the exceptional electrochemical activity and potential of Fe, N co-doped carbon polyhedrons for high-performance lithium-ion batteries. Carbonization of metal-organic frameworks and co-doping with Fe and N elements represents a promising strategy to enhance the electrochemical performance of graphitic carbon anode materials.