Hierarchical Ti3C2T@MoS2 heterostructures: A first principles calculation and application in corrosion/wear protection

Surface and interface engineering plays a crucial role in modulating the properties of materials, especially two-dimensional (2D) materials. Hence, a strategy, forming heterostructures with MoS2, is proposed to overcome the natural agglomeration of Ti3C2Tx MXene nanosheets. Most importantly, the interactions between Ti3C2Tx and MoS2 were elaborately investigated by first-principles calculations based on density functional theory (DFT) for the first time. The calculations demonstrate that van der Waals forces dominate the interface interactions of Ti3C2Tx and MoS2, rendering Ti3C2Tx@MoS2 heterostructures favorable stability. The Ti3C2Tx@MoS2 heterostructure composites were synthesized through a facile one-step hydrothermal method and exhibit a 2D hierarchical structure. Furthermore, the corrosion and tribological properties of epoxy composite coatings with varying proportions of Ti3C2Tx@MoS2 composites were studied in detail. As a result, the epoxy composite coating with 0.1 wt.% Ti3C2Tx@MoS2 composites (Ti3C2Tx@MoS2-0.1) exhibits excellent corrosion protection and antiwear performances. The Ti3C2Tx@MoS2-0.1 keeps the largest low-frequency impedance modulus (|Z|0.01 Hz) and coating resistance (Rc) during the whole immersion period. Its wear rate is 0.09 μm3/(N μm) under the load of 10 N, one half of that of pure epoxy coating (EP). This work further broadens the application of MXene-based heterostructure composites.