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Facile synthesis of Si/Ge/graphite@C composite with improved tap density and electrochemical performance† † Electronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d2ra06311e

ABSTRACT: Nanoengineering is one of the most effective methods to promote the lithium storage performance of silicon material, which suffers from huge volume changes and poor reaction kinetics during cycling. However, the commercial application of nanostructured silicon is hindered by its high manufacturing cost and low tap density. Herein, a Si/Ge/graphite@C composite was successfully synthesized by ball-milling with subsequent calcination. By introducing Ge, graphite and an amorphous carbon coating, both tap density and electrochemical performance are improved significantly. Benefiting from the synergetic effects of the above components, the Si/Ge/graphite@C composite delivers a reversibility capacity of 474 mA h g−1 at 0.2 A g−1 and stable capacity retention. A Si/Ge/graphite@C composite was synthesized by ball-milling and subsequent calcination. In the figure, the long-term cycling performance is displayed and the inset image is the tap density comparison of this sample with commercial graphite.

SUBMITTER: Chang L

PROVIDER: S-EPMC9769885 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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