MFe2O4 (M = Ni, Co) nanoparticles anchored on amorphous carbon coated multiwalled carbon nanotubes as anode materials for lithium-ion batteries.

One dimensional CNTs@C@MFe 2 O 4 (M = Ni, Co) composites have been rationally designed and fabricated via a facile solvothermal method and a calcination process. In the unique structure, amorphous carbon served as binder can increase the loading of MFe 2 O 4 on CNTs and strengthened the binding of MFe 2 O 4 and CNTs. As anode materials for lithium ion batteries, the CNTs@C@MFe 2 O 4 delivers a high specific capacity, excellent cycling stability and high rate capacity. The enhanced electrochemical performance can be attributed to the uniform dispersion of MFe 2 O 4 nanoparticles on the amorphous carbon coated CNTs, which can improve contact area between the MFe 2 O 4 nanoparticles and the electrolyte, enhance electrical conductivity, buffer the volume change maintain the structural integrity of the electrodes. Meanwhile, the lithiation and delithiation processes are systematically investigated by X-ray photoelectron spectroscopy analysis and transmission electron microscope technique. Furthermore, the efficient synthesis process developed here can also be extended to design and synthesize other transition metal oxides/carbon nanotube functional materials. [ABSTRACT FROM AUTHOR]