Carbon-coated Bi5Nb3O15 as anode material in rechargeable batteries for enhanced lithium storage

Abstract Bismuth can alloy with lithium to generate Li 3 Bi with the volumetric capacity of about 3765 mAh cm −3 (386 mAh g −1 ), rendering bismuth-based materials as attractive alloying-type electrode materials for rechargeable batteries. In this work, bismuth-based material Bi 5 Nb 3 O 15 @C is fabricated as anode material through a traditional solid-state reaction with glucose as carbon source. Bi 5 Nb 3 O 15 @C composite is well dispersed, with small particle size of 0.5–2.0 µm. The electrochemical performance of Bi 5 Nb 3 O 15 @C is reinforced by carbon-coated layer as desired. The Bi 5 Nb 3 O 15 @C exhibits a high specific capacity of 338.56 mAh g −1 at a current density of 100 mA g −1 . And it also presents an excellent cycling stability with a capacity of 212.06 mAh g −1 over 100 cycles at 100 mA g −1 . As a comparison, bulk Bi 5 Nb 3 O 15 without carbon-coating only remains 319.62 mAh g −1 at 100 mA g −1 , revealing poor cycle and rate performances. Furthermore, in-situ X-ray diffraction experiments investigate the alloying/dealloying behavior of Bi 5 Nb 3 O 15 @C. These insights will benefit the discovery of novel anode materials for lithium-ion batteries.