Synthesis of hierarchical N-doped porous carbon structure/nanospheres Fe2O3 composites and its application in lithium-ion battery as lithium-ion anodes

Nitrogen-doped porous carbons are of special interest, because their unique physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, and are thus very important for applications in the fields of catalysis, environment techniques and energy generation and storage. Moreover, nitrogen-doping can be further amplified in a porous structure that bears a high surface area to increases their materials performance in electrochemical devices, such as double layer capacitors and lithium-ion batteries. In addition, nitrogen-doping can enhance the lithium insertion, between the nitrogen-doped carbon material and lithium. And it can create a large number of defects in the porous configuration and offer more active sites for lithium insertion.
Toward this goal, a hierarchically structured macro- and mesoporous N-doped carbon with dispersed Fe2O3 nanoparticles (NDC@Fe2O3) is prepared by thermal treatment of a novel composite composed by PMMA particles decorated by graphene oxide (GO), PPy and iron salts. The NDC@Fe2O3 composite exhibited high surface area with a hierarchical pores structure. Integrated as a lithium ion battery anode, NDC@Fe2O3 exhibited high reversible capacity of 930 mA h/g over 200 cycles. The combination of Fe2O3 nanoparticles with nitrogen-doped porous carbons to form hybrid anode has been an efficient way to maintain the electronic integrity of the whole electrode since the carbon acts as a buffer layer to accommodate the volume variation and to provide multidimensional electron transport pathways during the charge/discharge process.