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Description
High-rate lithium-ion storage requires anodes with fast charge transport, accessible ion pathways, and stable interfaces. Here, an alkalization-assisted electrostatic self-assembly strategy is used to construct CoNi@MXene, in which Co/Ni hydroxide/oxide-like nanodomains are anchored on Ti3C2Tx MXene through deprotonated oxygen-containing surface sites. This multipoint interfacial anchoring suppresses MXene restacking, stabilizes redox-active domains, and preserves efficient electron/ion transport pathways. As a lithium-ion battery anode, CoNi@MXene delivers 1205 mAh g⁻1 at 0.1 A g⁻1 and maintains 696 mAh g⁻1 at 5 A g⁻1. During long-term cycling, it retains 203 mAh g⁻1 after 2000 cycles at 1 A g⁻1 and 179 mAh g⁻1 after 1800 cycles at 5 A g⁻1, with Coulombic efficiency approaching 100%. Kinetic and impedance analyses reveal dominant capacitive storage, facilitated Li+ diffusion, and a cycling-induced decrease in charge-transfer resistance from 149.8 to 20.4 Ω. Ex situ X-ray absorption spectroscopy (XAS) indicates the retained and electronically adaptive Co/Ni active sites after cycling, while density functional theory (DFT) calculations reveal favorable interfacial binding and enhanced electronic coupling near the Fermi level. This work demonstrates an interfacial anchoring strategy for stabilizing MXene-based anodes and accelerating lithium-storage kinetics.