Fe3O4 nanorods in N-doped carbon matrix with pseudo-capacitive behaviors as an excellent anode for subzero lithium-ion batteries

Abstract

Owing to its high theoretical capacity, abundant natural resources and environmental friendliness, Fe3O4 is regarded as a promising anode material for high performance lithium-ion batteries. In this work, two-dimensional Fe3O4 nanorods with an average length of 300 nm coated by N-doped carbon matrix (Fe3O4@NCm) have been synthesized through an in-situ polymerization and subsequent calcining process. Fe3O4@NCm composites especially the Fe3O4@NCm-60 deliver excellent lithium storage performance when used as anode materials in subzero lithium ion batteries. The Fe3O4@NCm-60 exhibits a high reversible capacity of 760 mAh g−1 after 900 cycles when tested at a current density of 1000 mA g−1 at −17 ± 2 °C, which is the best performance among Fe3O4-based anode materials for subzero lithium ion batteries. The results in this work give the reasons why the composites possess excellent electrochemical performance at low temperature and suggest a facile method for making Fe3O4@ heterogeneous-doped carbon composites, which can be used in subzero lithium-ion batteries. Most importantly, it also shed light on fabricating a series of metal oxides@ heterogeneous-doped carbon composites which can be used in subzero lithium-ion batteries or other energy storage fields.