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arXiv · 2205.04751

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

Ziyang Gan·Ioannis Paradisanos·Ana Estrada-Real·Julian Picker·Emad Najafidehaghani·Francis Davies·Christof Neumann·Cedric Robert·Peter Wiecha·Kenji Watanabe·Takashi Taniguchi·Xavier Marie·Arkady V. Krasheninnikov·Bernhard Urbaszek·Antony George·Andrey Turchanin
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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.

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Ziyang Gan, Ioannis Paradisanos, Ana Estrada-Real, Julian Picker, Emad Najafidehaghani, Francis Davies, Christof Neumann, Cedric Robert, Peter Wiecha, Kenji Watanabe, Takashi Taniguchi, Xavier Marie, Arkady V. Krasheninnikov, Bernhard Urbaszek, Antony George, Andrey Turchanin. 2022-05-10. One pot chemical vapor deposition of high optical quality large area monolayer Janus transition metal dichalcogenides. https://doi.org/10.1002/adma.202205226

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