NiSb/nitrogen-doped carbon derived from Ni-based framework as advanced anode for lithium-ion batteries

Antimony anode has attracted much attention owing to its low lithium-embedded platform and high specific capacity. However, the dramatic volume expansion during the insertion and detachment of Li+ seriously affects its application in lithium-ion batteries. In this work, NiSb alloy embedded in nitrogen-doped carbon (NiSb/C) derived from a Ni-based framework was synthesized by a simple hydrothermal reaction followed by annealing treatment. NiSb alloy nanoparticles could alleviate significant volume expansion during lithium/delithiation owing to the good buffering action of Ni. Nitrogen-doped carbon provides abundant active sites for Li+ and serves as a conductive network to accelerate electron transport. Moreover, the uniformly dispersed NiSb alloy particles and the nitrogen-doped carbon can effectively cooperate to retain the structural completeness of antimony, which promotes the cycling stability and high-rate performance of the NiSb/C anode. At a high density of 2 A g-1, the prepared NiSb/C anode exhibits a reversible specific capacity of 426 mAh g-1 after 450 cycles. It can also exhibit a superior rate capability of 387 mAh g-1 at 5.0 A g-1, which can provide a possibility for designing new anode materials for rechargeable batteries.