Ge-graphene-carbon nanotube composite anode for high performance lithium-ion batteries

A Ge-graphene-carbon nanotube composite electrode was constructed by germanium (Ge) nanoparticles anchored on reduced graphene oxide (Ge-RGO) intertwined with carbon nanotubes (CNT). In this unique structure, the graphene sheets improve the electrical conductivity and buffer severe volume changes. Additionally, the CNT mechanically binds together with Ge-RGO to maintain the integrity of the electrodes and stabilize the electric conductive network for the active Ge nanoparticles, leading to better cycling performance. As a result, the designed anode exhibits an outstanding energy capacity up to 863.8 mA h g(-1) at a current density of 100 mA g(-1) after 100 cycles and good rate performances of 1181.7, 1073.8, 1005.2, 872.0, 767.6, and 644.8 mA h g(-1) at current densities of 100, 200, 400, 800, 1600, and 3200 mA g(-1), respectively. Our results indicate that the hybrids exhibit considerably improved lithium storage performance.