MXene-reinforced Sb@C nanocomposites with synergizing spatial confinement architecture enabled ultra-stable and fast lithium ion storage

Abstract

Antimony (Sb) is recognized as a potential anode material for lithium-ion batteries due to its high theoretical capacity and adequate working potential. However, its application is hindered by the significant volume expansion during lithiation and low intrinsic conductivity, leading to considerable capacity fading and reduced rate capability. Herein, a unique MXene-reinforced Sb@C (MSC) nanocomposite is constructed via in-situ growing Sb-MOF over the conductive MXene substrate, followed by annealing. MXene substrate and MOF-derived carbon layer coupling effectively creates a continuous and conductive framework, encapsulating Sb nanoparticles. This unique architecture mitigates volume expansion, prevents particle aggregation, and enhances interfacial charge transfer, significantly improving the lithium storage performance of the MSC nanocomposite over its Sb@C (SC) counterpart. The MSC nanocomposite achieves a high capacity of 625 mAh g−1 at 100 mA g−1, superior rate capability of 305 mAh g−1 at 10 A g−1, as well as excellent cycling stability with a capacity retention of 84.4 % over 2000 continuous cycles. Additionally, a lithium-ion full batteries with MSC anode and LiFePO4 cathode demonstrates a capacity of 168.9 mAh g−1 at 100 mA g−1 and a maximum energy density of 381.2 Wh kg−1 based on the cathode mass, illustrating its promising potential for constructing high-performance lithium ion batteries.