Quantification of defects engineered in single layer MoS 2

Aryeetey, Frederick; Ignatova, Tetyana; Aravamudhan, Shyam

doi:10.1039/d0ra03372c

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DOE OSTI · 1903908

Quantification of defects engineered in single layer MoS 2

Aryeetey, Frederick·Ignatova, Tetyana·Aravamudhan, Shyam

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Abstract

Atomic defects are controllably introduced in suspended single layer molybdenum disulfide (1L MoS 2 ) using helium ion beam. Vacancies exhibit one missing atom of molybdenum and a few atoms of sulfur. Quantification was done using a Scanning Transmission Electron Microscope (STEM) with an annular detector. Experimentally accessible inter-defect distance was employed to measure the degree of crystallinity in 1L MoS 2 . A correlation between the appearance of an acoustic phonon mode in the Raman spectra and the inter-defect distance was established, which introduces a new methodology for quantifying defects in two-dimensional materials such as MoS 2 .

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Aryeetey, Frederick, Ignatova, Tetyana, Aravamudhan, Shyam. 2020-06-16. Quantification of defects engineered in single layer MoS 2. https://doi.org/10.1039/d0ra03372c

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