Synthesis and Physical Properties of Two-Dimensional Cu₂Te Nanosheets

As a family member of copper monochalcogenides, the synthesis and physical property of the Cu₂Te crystal have never been reported before. In this paper, we theoretically study the Cu₂Te crystal structure using a first-principles approach. Using a salt-assisted chemical vapor deposition method, we successfully realize the rational synthesis of the high-quality crystal of layered Cu₂Te nanosheets. The energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy characterizations confirm the chemical composition of our as-grown Cu₂Te nanosheets. The transmission electron microscopy characterization proves the crystal structure of the as-grown Cu₂Te nanosheets. Raman spectroscopy reveals the novel evolution of the phonon scattering as a function of the as-grown Cu₂Te layer thickness compared to that of Cu₂S and Cu₂Se. Our work provides a way for copper monochalcogenides to explore novel physical phenomena and tremendous potentiality in the application of functional nanoelectronics.