One pot chemical vapor deposition of high optical quality large area monolayer Janus transition metal dichalcogenides

Abstract

We report one-pot chemical vapor deposition (CVD) growth of large-area Janus SeMoS monolayers, with the asymmetric top (Se) and bottom (S) chalcogen atomic planes with respect to the central transition metal (Mo) atoms. The formation of these two-dimensional semiconductor monolayers takes place upon the thermodynamic equilibrium-driven exchange of the bottom Se atoms of the initially grown MoSe2 single crystals on gold foils with S atoms. The growth process is characterized by complementary experimental techniques including Raman and X-ray photoelectron spectroscopy and the growth mechanisms are rationalized by first principle calculations. The remarkably high optical quality of the synthesized Janus monolayers is demonstrated by optical and magneto-optical measurements which reveal the strong exciton-phonon coupling and enable to obtain the exciton g-factor of -3.3.

References in corpus (9)

• k.p theory for two-dimensional transition metal dichalcogenide semiconductors
• Valley Splitting and Polarization by the Zeeman Effect in Monolayer MoSe2
• Synthesis of epitaxial monolayer Janus SPtSe
• Controlling interlayer excitons in MoS2 layers grown by chemical vapor deposition
• Raman spectrum of Janus transition metal dichalcogenide monolayers WSSe and MoSSe
• Designing Artificial Two-Dimensional Landscapes via Room-Temperature Atomic-Layer Substitution
• Guide to optical spectroscopy of layered semiconductors
• Efficient phonon cascades in hot photoluminescence of WSe${}_2$ monolayers
• Magneto-spectroscopy of exciton Rydberg states in a CVD grown WSe2 monolayer

Cited by in corpus (4)

• Exciton spectroscopy and diffusion in MoSe2-WSe2 lateral heterostructures encapsulated in hexagonal boron nitride
• Nonlinear Dispersion Relation and Out-of-Plane Second Harmonic Generation in MoSSe and WSSe Janus Monolayers
• Atomically-precise synthesis and simultaneous integration of 2D transition metal dichalcogenides enabled by nano-confinement
• Tunable resonant s-p mixing of excitons in van der Waals heterostructures