Chemical synthesis of porous hierarchical Ge–Sn binary composites using metathesis reaction for rechargeable Li-ion batteries

Abstract

Direct metathesis reaction between Mg₂Ge and SnCl₄ is introduced to prepare porous hierarchical Ge–Sn binary composites, in which the Ge and Sn components are distributed uniformly, with a tap density of 2.3 g cm⁻³. As an anode for LIBs, the Ge–Sn composite displays a specific capacity of 980 mA h g⁻¹ at 0.5 A g⁻¹ after 250 cycles, and 890 mA h g⁻¹ at 3 A g⁻¹ over 1700 cycles. When paired with a commercial LiCoO₂ cathode, a 3.6 V full battery with a capacity of 830 mA h g⁻¹ is obtained.