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Lattice strain effects on the optical properties of MoS2 nanosheets.

ABSTRACT: "Strain engineering" in functional materials has been widely explored to tailor the physical properties of electronic materials and improve their electrical and/or optical properties. Here, we exploit both in plane and out of plane uniaxial tensile strains in MoS2 to modulate its band gap and engineer its optical properties. We utilize X-ray diffraction and cross-sectional transmission electron microscopy to quantify the strains in the as-synthesized MoS2 nanosheets and apply measured shifts of Raman-active modes to confirm lattice strain modification of both the out-of-plane and in-plane phonon vibrations of the MoS2 nanosheets. The induced band gap evolution due to in-plane and out-of-plane tensile stresses is validated by photoluminescence (PL) measurements, promising a potential route for unprecedented manipulation of the physical, electrical and optical properties of MoS2.

SUBMITTER: Yang L

PROVIDER: S-EPMC4090623 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Lattice strain effects on the optical properties of MoS2 nanosheets.

Yang Lei L Cui Xudong X Zhang Jingyu J Wang Kan K Shen Meng M Zeng Shuangshuang S Dayeh Shadi A SA Feng Liang L Xiang Bin B

Scientific reports 20140710

"Strain engineering" in functional materials has been widely explored to tailor the physical properties of electronic materials and improve their electrical and/or optical properties. Here, we exploit both in plane and out of plane uniaxial tensile strains in MoS2 to modulate its band gap and engineer its optical properties. We utilize X-ray diffraction and cross-sectional transmission electron microscopy to quantify the strains in the as-synthesized MoS2 nanosheets and apply measured shifts of ...[more]

PMID: 25008782

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