High lithium anodic performance of highly nitrogen-doped porous carbon prepared from a metal-organic framework

Theoretical and experimental results have revealed that the lithium-ion storage capacity for nitrogen-doped graphene largely depends on the nitrogen-doping level. However, most nitrogen-doped carbon materials used for lithium-ion batteries are reported to have a nitrogen content of approximately 10 wt% because a higher number of nitrogen atoms in the two-dimensional honeycomb lattice can result in structural instability. Here we report nitrogen-doped graphene particle analogues with a nitrogen content of up to 17.72 wt% that are prepared by the pyrolysis of a nitrogen-containing zeolitic imidazolate framework at 800 °C under a nitrogen atmosphere. As an anode material for lithium-ion batteries, these particles retain a capacity of 2,132 mA h g−1 after 50 cycles at a current density of 100 mA g−1, and 785 mAh g−1 after 1,000 cycles at 5 A g−1. The remarkable performance results from the graphene analogous particles doped with nitrogen within the hexagonal lattice and edges.