Ultrafine Sn nanocrystals in a hierarchically porous N-doped carbon for lithium ion batteries

We report a simple method of preparing a high performance, Sn-based anode material for lithium ion batteries (LIBs). Adding H₂O₂ to an aqueous solution containing Sn²⁺ and aniline results in simultaneous polymerization of aniline and oxidation of Sn²⁺ to SnO₂, leading to a homogeneous composite of polyaniline and SnO₂. Hydrogen thermal reduction of the above composite yields N-doped carbon with hierarchical porosity and homogeneously distributed, ultrafine Sn particles. The nanocomposite exhibits excellent performance as an anode material for lithium ion batteries, showing a high reversible specific capacity of 788 mAh·g^-1 at a current density of 100 mA·g^-1 after 300 cycles and very good stability up to 5, 000 mA·g^-1. The simple preparation method combined with the good electrochemical performance is highly promising to promote the application of Sn based anode materials.