Metal-organic frameworks-derived CoFe2O4/Ti3C2Tx MXene/carbon nanofibers for high-rate lithium-ion batteries

CoFe2O4 is recognized as a prospective anodes material for lithium-ion batteries (LIBs) due to its high theoretical capacities. However, challenges such as volume expansion, low conductivity and slow electrochemical kinetics are suffered. In this study, Ti3C2Tx coupled metal-organic frameworks (MOF)-derived porous CoFe2O4, integrated with carbon nanofibers (CNFs) through electrospinning followed by calcination. The resulting composite exhibits outstanding theoretical capacity and enhanced conductivity. The layered structure of Ti3C2Tx significantly increased the mass loading of CoFe2O4, while CoFe2O4 in turn prevents the restacking of Ti3C2Tx MXene layers. In addition, the CNFs provide an intertwined network, increasing specific surface area and offering more fast transport pathways for Li-ions, thereby improving the loading and reaction sites of active materials. The 3D structured composite effectively mitigates volume expansion during charge/discharge along with improved conductivity, exhibiting exceptional rate performance and superb capacity as anode for LIBs. Specifically, MOF-derived CoFe2O4/Ti3C2Tx MXene/CNFs composite deliveries a notable rate performance of 332 mAh g(-1) at 20 A g(-1) and excellent long cycling stability with a sustained capacity of 972 mAh g(-1) at 2 A g(-1) even after 1000 cycles.