Exfoliation and Reassembly Routes to a Ge/RuO(2) Nanocomposite as an Anode for Advanced Lithium-Ion Batteries

Ge/RuO(2) nanocomposites were successfully fabricated as anode materials for lithium-ion batteries using RuO(2) nanosheets and Ge/GeO(2) nanoparticles (NPs). X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) analyses showed that elemental Ge nanoparticles were distributed onto the rutile-type RuO(2). Transmission electron microscopy images showed well-dispersed Ge nanoparticles embedded in rutile-type RuO(2). The Ge/RuO(2) nanocomposite maintained higher discharge capacities (471 mA h g(−1)) after the 90th cycle at 0.1 A g(−1) than that (211 mA h g(−1)) of Ge/GeO(2) nanoparticles. The Ge/RuO(2) nanocomposite exhibited a higher capacity retention than Ge/GeO(2) NPs. These results suggest that the well-dispersed Ge nanoparticles within RuO(2) matrices enhance the cycle stability and capacity retention of the anode material.