Self-Assembled Moiré Superlattices of TiCT MXene for Future Twistronic Applications.

Nanoscale periodic Moiré superlattices based on 2D heterostructures offer an opportunity to unveil and exploit electronic and quantum properties that are not present in single-layer 2D and/or 3D bulk counterparts. However, a detailed understanding of the Moiré superlattices and their resulting electronic structure at the atomic scale is currently lacking in many systems, such as the fastest-growing family of 2D materials, MXenes. This is crucial for gaining fundamental knowledge and mastery over quantum phenomena in these materials. This study thoroughly examines and compares the self-assembled Moiré superlattices of the most prominent MXene, TiCT, by combining experimental scanning tunneling microscopy and spectroscopy with density functional theory calculations. Three distinct self-assembled Moiré patterns with a periodicity of 2.52, 2.39, and 1.25 nm are investigated. Experimental and theoretical data reveal that the Moiré superlattice with a periodicity of 1.25 nm exhibits a spatial modulation of the density of states in the conduction band due to electronic interlayer coupling effects. The findings unveil MXene Moiré superlattices at the atomic level and pave the way to a new research field in MXetronics and twistronics with great potential for quantum devices and related applications.