Breaking the Thick Electrode Paradox With an in situ VS₂@V₂CTx MXene Heterostructure for High-Areal-Capacity...

Achieving high areal capacity is critical for advancing lithium-ion batteries (LIBs) toward high-energy-density applications. However, prevailing thick electrode architectures inevitably suffer from sluggish charge transport kinetics and mechanical degradation. Here, we pioneer an in situ gas-phase conversion strategy to directly grow metallic VS₂ nanosheets on V₂CTx MXene within a multi-walled carbon nanotube (MWCNT) network. This integrated architecture simultaneously establishes interpenetrating electron/ion highways-enabling full lithiation in ultra-thick electrodes (12-fold higher Li⁺ concentration compare to the traditional electrode)-and enhances mechanical toughness, thus achieving exceptional cycling stability under high current densities. Such TMDC-MXene heterostructure exhibit an impressive specific capacity of 1046 mAh g^-1 and areal capacity of 13.6 mAh cm^-2, with the thickness of 300 µm, representing only 12.8% gravimetric capacity decay despite 333% increased electrode thickness. Moreover, the resulting electrode maintains excellent cycling stability, retaining a capacity of 1.8 mAh cm^-2 even at high current density of 6.4 mA cm^-2, alongside 81% capacity retention over 600 cycles at 2C in LiFePO₄ full-cells.