Dual Confinement of Si Nanoparticles in a MXene/ZIF-8-Derived Carbon Framework for Lithium-Ion Batteries

Silicon (Si) shows great potential for lithium-ion batteries (LIBs) due to its high theoretical capacity and low working potential. However, its intrinsic low electronic conductivity and large volume expansion during lithiation result in dramatic capacity fading and poor rate capability. Herein, a dual-confinement strategy is proposed for improving the lithium storage properties of Si by uniformly anchoring Si nanoparticles within a MXene/ZIF-8 derived carbon framework. In the Si/MXene@C composite, Si nanoparticles tightly bond with MXene and carbon through the formed interfacial Si–O–Ti and Si–C bonds, respectively, which is beneficial for alleviating the volume expansion of Si and promoting the interfacial charge transfer. Therefore, the Si/MXene@C composite exhibits excellent lithium storage performances in terms of high capacity (1006.1 mAh g–1 at 100 mA g–1), stable cycle performance (862.9 mAh g–1 after 150 cycles at 100 mA g–1), and superior rate capability (233.3 mAh g–1 at 5 A g–1), indicating its promising potential as an anode material for next-generation high-performance LIBs.