Exfoliation and Reassembly Routes to a Ge/RuO2 Nanocomposite as an Anode for Advanced Lithium-Ion Batteries

Abstract

Ge/RuO2 nanocomposites were successfully fabricated as anode materials for lithium-ion batteries using RuO2 nanosheets and Ge/GeO2 nanoparticles (NPs). X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) analyses showed that elemental Ge nanoparticles were distributed onto the rutile-type RuO2. Transmission electron microscopy images showed well-dispersed Ge nanoparticles embedded in rutile-type RuO2. The Ge/RuO2 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/GeO2 nanoparticles. The Ge/RuO2 nanocomposite exhibited a higher capacity retention than Ge/GeO2 NPs. These results suggest that the well-dispersed Ge nanoparticles within RuO2 matrices enhance the cycle stability and capacity retention of the anode material.