Two-dimensional (2D) kagome materials have attracted considerable attention due to their unique electronic properties. Based on first-principles calculations and employing the "1+3" design strategy, we designed a class of composition-tunable 2D multilayer kagome materials, V6SnSe6-nCl6, and identified four stable structures: V6Se6Cl6, V6S2Se4Cl6, V6S3Se3Cl6, and V6S5Se1Cl6. 2D V6SnSe6-nCl6possesses three kagome layers, two of which are vanadium-based kagome layers, and the other is a sulfur or selenium atomic layer. Electronic structure analysis reveals that 2D V6SnSe6-nCl6is a narrow direct-bandgap semiconductor with a bandgap ranging from 0.568 to 0.742 eV, and exhibits ultrahigh electron mobility up to 4×104cm2V-1s-1. Orbital analysis further demonstrates that the bands contributed by the V-based kagome layers form flat bands and Dirac cones below the Fermi level, and show a relatively high band velocity. In summary, 2D V6SnSe6-nCl6provides an excellent platform for kagome physics research and the fabrication of nanoelectronic devices, adaptable to various device scenarios.
Wang∗ et al. (Fri,) studied this question.