Enhancing MXene-Based anodes with two-dimensional VO2/V2CO2 heterostructures: A first-principles calculations study

Abstract

The integration of MXene with complementary two-dimensional materials to form heterostructures has the potential to improve the electrochemical performance of MXene. In our study, we constructed a van der Waals heterostructure composed of VO₂/V₂CO₂, and evaluated its effectiveness as an anode material for Li, Na, and Mg ion batteries through first-principles density functional theory simulations. Our findings reveal that the VO₂/V₂CO₂ heterostructure demonstrates exceptional stability and inherent metallic characteristics. We identified diffusion barriers for Li, Na, and Mg ions within the interlayer to be relatively low—at 0.38 eV, 0.22 eV, and 0.51 eV, respectively—suggesting efficient ion transport. Furthermore, the average open-circuit voltages (OCVs) for Li-ion, Na-ion, and Mg-ion batteries were found to be between 0 and 1.5 V, which is advantageous for inhibiting lithium dendrite growth. Remarkably, the heterostructure showcases a theoretical storage capacity reaching up to 585mA h/g for Li, 351 mA h/g for Na, and an impressive 936 mA h/g for Mg adsorption—outstripping the capabilities of graphite and surpassing several other two-dimensional materials. These compelling results underscore the VO₂/V₂CO₂ heterostructure as a highly promising anode material, particularly for Li-ion and Mg-ion battery applications.