Interlayer-Decoupled Sc-Based Mxene with High Carrier Mobility and Strong Light-Harvesting Ability.

Two-dimensional (2D) van der Waals (vdW) layered materials offer a unique combination of electronic and structural properties attractive for technological applications. Most of them show strong vdW interactions, which lead to interlayer-coupled optoelectronic properties due to quantum confinement. Here we present a systematic computational study of one Mxene, 2D double-metal-layered scandium chloride carbides (Sc2CCl2). Unlike conventional quantum-confined nanosystems, 2D Sc2CCl2 exhibits weak vdW interactions with robust interlayer-decoupled optoelectronic properties and extremely high and anisotropic carrier mobilities of about 1-4.5 × 104 cm2 V-1 s-1 that consequently produce comparatively large drain currents. Specifically, the 2D Sc2CCl2 family has strong light-harvesting ability and could be utilized as efficient donor materials in excitonic solar cells. Overall, in combination with high structural stability against ambient conditions, interlayer-decoupled robust optoelectronic properties potentially relax the requirements for the fabrication of high-quality monolayers and for selection of suitable substrates and suggest promising next-generation optoelectronic applications.