Freeze-Drying-Assisted Synthesis of Hierarchically Porous Carbon/Germanium Hybrid for High-Efficiency Lithium-Ion Batteries

Herein, an approach is reported to prepare porous a carbon/Ge (C/Ge) hybrid. In this hybrid, Ge nanoparticles are closely embedded in a highly conductive and flexible carbon matrix. Such a hybrid features a high surface area (128.0m(2)g(-1)) and a hierarchical micropore-mesopore structure. When used as an anode material in lithium-ion batteries (LIBs), the as-prepared hybrid [C/Ge (60.37%)] exhibits an improved lithium storage performance with regard to its capacity and rate capability compared to its counterparts. More specifically, it can maintain a specific capacity as high as 906mAhg(-1) at a high current density of 0.6Ag(-1) after 50cycles. The excellent lithium storage performance of the C/Ge (60.37%) sample can be attributed to synergetic effects between the carbon matrix and Ge nanoparticles. The method we adopted is simple and effective, and can be extended to fabricate other nanomaterials.