Embedded into Graphene Ge Nanoparticles Highly Dispersed on Vertically Aligned Graphene with Excellent Electrochemical Performance for Lithium Storage

Decreasing particle size has always been reported to be an efficient way to improve cyclability of Li-alloying based LIBs. However, nanoparticles (NPs) tend to agglomerate and evolve into lumps, which in turn limits the cycling performance. In this report, we prepared a unique nanostructure, graphene-coated Ge NPs are highly dispersed on vertically aligned graphene (Ge@graphene/VAGN), to avoid particle agglomeration and pulverization. Remarkable structure stability of the sample leads to excellent cycling stability. Upon cycling, the anode exhibits a high capacity of 1014 mAh g(-1), with nearly no capacity loss in 90 cycles. Rate performance shows that even at the high current density of 13 A g(-1), the anode could still deliver a higher capacity than that of graphite.