Zn–Fe–ZIF-derived porous ZnFe2O4/C@NCNT nanocomposites as anodes for lithium-ion batteries

A novel hybrid of porous ZnFe2O4/carbon (C)@nitrogen-doped carbon nanotube (NCNT) nanocomposites with a high surface area of 256 m2 g−1 is synthesized by a one-step pyrolysis of Zn–Fe–ZIF as a precursor and sacrificial template. The porous ZnFe2O4/C@NCNT nanocomposites, possessing a large carbon content of about 50 wt%, deliver an initial discharge of 2192 mA h g−1 and still reach a high reversible capacity of 844 mA h g−1 after 100 cycles at a current density of 100 mA g−1. The sample also exhibits an exceptional rate capability of 747 mA h g−1 at a large current density of 1 A g−1. The unusual construction in which ZnFe2O4 nanoparticles are homogeneously distributed in the entire carbon framework coated by NCNTs may mainly contribute to the good electrochemical performance. Therefore, the resulting porous ZnFe2O4/C@NCNT nanocomposites are potentially useful for rechargeable LIBs.