Galvanic Replacement Preparation of Spindle-Structured Sb@C@NC as Anode for Superior Lithium-Ion Storage

Abstract

Antimony (Sb) is regarded to be a potential alloying-type anode for lithium-ion batteries due to its excellent electrochemical reversibility and high theoretical specific capacity (660 mA h g−1). However, huge volume expansion accompanying rapid capacity fading seriously hinders its commercial application. Herein, double-carbon-modified spindle-structured Sb@C@NC were constructed via galvanic replacement using a Fe-based metal-organic framework (MOF) with polydopamine-coated-derived Fe@C@NC as reactants. Due to the unique double-carbon-encapsulated structure, the Sb@C@NC anode effectively moderates the volume fluctuation and maintains the integral framework from collapsing during the annealing and cycling process. As lithium-ion battery (LIB) anodes, Sb@C@NC attained excellent cycling performance (389 mAh g−1 at 100 mA g−1 after 100 cycles) and superior rate capability (a reversible capacity of 343 mAh g−1 at 2000 mA g−1). Such an MOF-based approach provides an adjustable strategy for Sb-based nanomaterial and shield light on the applications of Sb@C@NC in other fields.