Highly mesoporous and chemically bonded Fe3O4/N-doped carbon nanocomposite with an outstanding cycling life as lithium-ion-battery anode

Abstract

Owing to high theoretical capacity (926 mAh g−1), Fe3O4 has achieved much focus as a prospective anode material for lithium-ion batteries (LIBs). A one-step vapor-pressured induced approach considering the synthesis of chemically bonded Fe3O4/N-doped carbon nanocomposites (Fe3O4/NC) via Fe-O-C and Fe-N-C, together with the encapsulation of Fe3O4 nanoparticles (∼80 nm) into highly mesoporous N-doped carbon matrix via pyrolyzing the mixture of iron oxalate and dimethylformamide in a sealed vessel, does not exist at present. As LIB anode, the Fe3O4/NC presents a high capacity of 1250.2 mAh g−1 at 0.1 A g−1, an outstanding cyclability with a capacity of 600.1 mAh g−1 after 4000 cycles at 5 A g−1, and a high rate capability (244.8 mAh g−1 at 20 A g−1). Such excellent performances can be ascribed to its unique structure that Fe3O4 nanoparticles tightly encapsulated into highly mesoporous N-doped carbon matrix can increase active sites, electrical conductivity, and cyclability.