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DOE OSTI · 2573426

Van der Waals Sandwich Structures for Surface-Enhanced Raman Scattering

Wei, Youchao [Chongqing Univ. (China)]·Wang, Shuo [Chongqing Univ. (China)]·Zhang, Zhaofu [Wuhan Univ. (China)] (ORCID:0000000214061256)·Zang, Zhigang [Chongqing Univ. (China)] (ORCID:000000031632503X)·Liang, Liangbo [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)] (ORCID:0000000311990049)·Huang, Shengxi [Rice Univ., Houston, TX (United States)] (ORCID:0000000236189074)·Qian, Qingkai [Chongqing Univ. (China)] (ORCID:0000000175130676)
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Abstract

Surface-enhanced Raman scattering (SERS) intensity of two-dimensional (2D) materials critically depends on the resonant conditions and factors such as the substrate interferences and molecule adsorption fluctuations, making comprehensive investigation, understanding, and optimization of 2D materials-assisted SERS challenging. Here, in this work, the wavelength-dependent SERS of van der Waals structures of 2D materials is systematically investigated, focusing on the intrinsic frequency-dependent Raman tensors by first-principles method while ruling out other extrinsic factors in experiments. Distinct enhancement profiles are found for different 2D materials, among which MoS2 and graphene exhibit remarkably strong and broadband enhancement effects. For stacked multilayers and heterostructures of 2D materials, the calculated SERS addresses the significance of the first contact monolayer effect. Based on the above theory, the van der Waals sandwich structures are proposed and investigated as the SERS substrates, verifying a further significantly enhanced SERS performance. This resonant first-principles study demonstrates a comprehensive and analytical way to explore and promote the SERS of van der Waals structures.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYRaman spectroscopyaromatic compoundshydrocarbonsmoleculestwo dimensional materials

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Wei, Youchao [Chongqing Univ. (China)], Wang, Shuo [Chongqing Univ. (China)], Zhang, Zhaofu [Wuhan Univ. (China)] (ORCID:0000000214061256), Zang, Zhigang [Chongqing Univ. (China)] (ORCID:000000031632503X), Liang, Liangbo [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)] (ORCID:0000000311990049), Huang, Shengxi [Rice Univ., Houston, TX (United States)] (ORCID:0000000236189074), Qian, Qingkai [Chongqing Univ. (China)] (ORCID:0000000175130676). 2025-03-24. Van der Waals Sandwich Structures for Surface-Enhanced Raman Scattering. https://doi.org/10.1021/acs.jpcc.5c00101

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