Thin-walled graphitic nanocages with nitrogen-doping as superior performance anodes for lithium-ion batteries

N-Doped nanocages with thin-walled graphitic shells (∼1.2 nm) were synthesized by removing the ferrous cores of Fe@C nanoparticles. The Fe@C nanopores were prepared by floating catalytic pyrolysis with the N atoms being in situ doped in their graphitic shells. Due to the thin-walled graphitic shells of the nanocages, the fast distribution of the electrolyte and ions was achieved and the prepared nanocage-based anode of lithium-ion batteries showed excellent performance: a high reversible specific capacity (after 50 cycles; 760 mA h g−1 at 0.5 A g−1) and a remarkable rate capability (after 40 cycles; 250 mA h g−1 at 10 A g−1).