Epitaxial Growth of Monolayer PdTe₂ and Patterned PtTe₂ by Direct Tellurization of Pd and Pt surfaces

Two-dimensional (2D) palladium ditelluride (PdTe₂) and platinum ditelluride (PtTe₂) are two Dirac semimetals which demonstrate fascinating quantum properties such as superconductivity, magnetism and topological order, illustrating promising applications in future nanoelectronics and optoelectronics. However, the synthesis of monolayer materials is dramatically hindered by strong interlayer coupling and orbits hybridization. Here, a protocol for the synthesis of monolayer PdTe₂ and PtTe₂ is demonstrated. Epitaxial growth of large-area and high quality monolayers of PdTe₂ and patterned PtTe₂ is achieved by direct tellurization of Pd(111) and Pt(111), respectively. More interestingly, in the case of PtTe₂, different monolayer patterns are obtained by inducing Te vacancies during growth. A well-ordered (2×2) PtTe₂ pattern formed by Te vacancy arrays is successfully grown by controlling the density of defects. The simple and reliable growth procedure of monolayer PdTe₂ and patterned PtTe₂ gives unprecedented opportunities for investigating new quantum phenomena and facilitating practical applications in electronics and catalysts.