Carbon-coated graphite nanosheet-hosted SnO2-BaTiO3 heterojunctions: A high-capacity and long-cycle-stable anode material for lithium-ion batteries

SnO 2 is considered a promising anode material for lithium-ion batteries (LIBs) due to its significant theoretical capacity derived from alloying and conversion reactions for lithium storage. However, its development is hindered by considerable volume changes, sluggish kinetics, and limited reversibility of the conversion reaction. In this study, carbon-encapsulated graphite nanosheets-hosted SnO 2 -BaTiO 3 composites (C@SnO 2 -BaTiO 3 -G) with heterojunction structure were synthesized by simple ball milling and calcination, and the material as anode for LIBs exhibits a high specific capacity of 1367.7 mAh g −1 after 200 charge-discharge cycles at a current density of 0.1 A g −1 . Even at a high current density of 5 A g −1 , after 2500 long-cycle tests, its specific capacity can still remain at 401.7 mAh g −1 . The addition of BaTiO 3 can effectively enhance the conversion reactions of SnO 2 . The outer carbon layer and graphite nanosheets serve to protect the structure of the composite material during cycling, preventing agglomeration and coarsening. The C@SnO 2 -BaTiO 3 -G composite material effectively addresses the shortcomings of SnO 2 , making it an excellent anode material for high-performance LIBs.