Nanostructured metal phosphides are very attractive materials in energy storage and conversion, but their applications are severely limited by complicated preparation steps, harsh conditions and large excess of highly toxic phosphorus source. Here we develop a highly efficient one-step method to synthesize Sn₄P₃ nanostructure based on simultaneous reduction of SnCl₄ and PCl₃ on mechanically activated Na surface and in situ phosphorization. The low-toxic PCl₃ displays a very high phosphorizing efficiency (100%). Furthermore, this simple method is powerful to control phosphide size. Ultrafine Sn₄P₃ nanocrystals (< 5 nm) supported on carbon sheets (Sn₄P₃/C) are obtained, which is due to the unique bottom-up surface-limited reaction. As the anode material for sodium/lithium ion batteries (SIBs/LIBs), the Sn₄P₃/C shows profound sodiation/lithiation extents, good phase-conversion reversibility, excellent rate performance and long cycling stability, retaining high capacities of 420 mAh/g for SIBs and 760 mAh/g for LIBs even after 400 cycles at 1.0 A/g. Combining simple and efficient preparation, low-toxic and high-efficiency phosphorus source and good control of nanosize, this method is very promising for low-cost and scalable preparation of high-performance Sn₄P₃ anode.

Magnesium hydride (MgH₂) is a high-capacity anode material for lithium ion batteries, which suffers from poor cycling stability. In this study, we describe a thermal plasma-based approach to prepare homogeneous MgH₂/C nanocomposites with very high cycling stability. In this process, magnesium evaporation is coupled with carbon generation from the plasma decomposition of acetylene, leading to a homogeneous Mg/C nanocomposite, which can be easily converted to MgH₂/C by hydrogenation. The MgH₂/C nanocomposite achieves a high reversible capacity of up to 620 mAh·g^–1 after 1, 000 cycles with an ultralow decay rate of only 0.0036% per cycle, which represents a significantly improved performance compared to previous results.

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.