Hollow carbon nanosphere embedded with ultrafine Fe3O4 nanoparticles as high performance Li-ion battery anode

- Hollow carbon nanospheres embedded with ultrafine Fe3O4 nanoparticles (Fe3O4@HCNS) were synthesized.
- The Fe3O4@HCNS exhibited high reversible capacity, excellent cycling stability and high-rate capability.
- The ultrafine Fe3O4 NPs ensured small volume change and shorten the path of Li ions intercalation.
- The mesoporous HCNS alleviated the volume change and protected the ultrafine Fe3O4 NPs from aggregation.

Hollow carbon nanospheres embedded with ultrafine Fe3O4 nanoparticles (Fe3O4@HCNS) were synthesized by using carboxyl functionalized polystyrene latexes as template and poly dopamine as carbon precursor. The ultrafine Fe3O4 nanoparticles (NPs) had a small size of 3 ∼ 5 nm and the HCNS had a thin shell thickness of 15 nm in the Fe3O4@HCNS. As a promising anode material for lithium-ion batteries, the Fe3O4@HCNS exhibited high reversible capacity, excellent cycling stability (1380 mA h g−1 after 200 cycles at 1 A g−1) and high-rate capability (475 mA h g−1 at 5 A g−1, 290 mA h g−1 at 10 A g−1). The outstanding performance was attributed to the unique structure of the Fe3O4@HCNS, which greatly shorten the path of Li ions intercalation during charging and discharging.

Hollow carbon nanospheres embedded with ultrafine Fe3O4 nanoparticles (Fe3O4@HCNS) were synthesized by using carboxyl functionalized polystyrene latexes as template and polydopamine as carbon precursor for high performance Li-ion battery anode.123