Amorphous Ge/C Composite Sponges: Synthesis and Application in a High-Rate Anode for Lithium Ion Batteries

A Ge/C spongelike composite is prepared by the facile and scalable single-step pyrolysis of the GeO_x/ethylenediamine gel process, which has a feature with three-dimensional interconnected pore structures and is hybridized with nitrogen-doped carbon. A detailed investigation shows that the pore in the sponge is formed for the departure of the gaseous products at the evaluated temperature. As an anode for lithium ion batteries, the obtained composite exhibits superior specific capacity in excess of 1016 mA h g^-1 at 100 mA g^-1 after 100 cycles. Moreover, the amorphous Ge/C sponge electrode also has a good rate capacity and stable cycling performance. The obtained amorphous Ge/C sponges are a good candidate anode for next-generation lithium ion batteries.