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DOE OSTI · 2587066

Twists and turns: stacking and structure-dependent optical response in MoS 2 nanoscrolls

Abstract

Transition metal dichalcogenide (TMD) nanoscrolls (NSs), specifically MoS 2 NSs, present unique structural and optical properties, exhibiting prominent photoluminescence (PL) signals despite their multilayer nature. Here, this study investigates the structural and spectroscopic characteristics of MoS 2 NSs, correlating them to show the effects of reduced interlayer interactions on excitons of MoS 2 NSs. The reduction in interlayer interaction arises from two main factors: (1) symmetry-broken mixed stacking due to misalignment between layers and (2) a highly inhomogeneous strain profile generated by the Archimedean spiral geometry with positive eccentricity. Transmission electron microscopy, field emission scanning electron microscopy, atomic force microscopy, Raman spectroscopy, and second harmonic generation measurements confirm these findings. Low-temperature PL spectroscopy explores the impact of reduced interlayer interactions on exciton properties such as exciton–phonon coupling and oscillator strength. This study provides crucial insights into the structure, stacking and unique optical properties of TMD NSs, advancing the understanding of interlayer interactions and their impacts in complex quasi-one-dimensional nanostructures.

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BibTeXRIS

Chatterjee, Sagnik [Indian Institute of Science Education and Research (IISER), Pune (India)] (ORCID:0009000209368680), Chowdhury, Tamaghna [Indian Institute of Science Education and Research (IISER), Pune (India); Univ. of Manchester (United Kingdom)] (ORCID:0000000314028648), Díaz-Núñez, Pablo [Univ. of Manchester (United Kingdom)] (ORCID:0000000315116252), Kay, Nicholas [Univ. of Manchester (United Kingdom)] (ORCID:0009000533281990), Rajput, Manisha [Indian Institute of Science Education and Research (IISER), Pune (India)] (ORCID:0000000276551795), Mondal, Mainak [Indian Institute of Technology (IIT), Bangalore (India)] (ORCID:0000000211551620), Hwang, Sooyeon [Brookhaven National Laboratory (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)] (ORCID:0000000156066728), Timokhin, Ivan [Univ. of Manchester (United Kingdom)] (ORCID:0000000195539313), Singh, Akshay [Indian Institute of Technology (IIT), Bangalore (India)] (ORCID:000000031059065X), Mishchenko, Artem [Univ. of Manchester (United Kingdom)] (ORCID:0000000204275664), Rahman, Atikur [Indian Institute of Science Education and Research (IISER), Pune (India)] (ORCID:0000000212757129). 2025-07-14. Twists and turns: stacking and structure-dependent optical response in MoS 2 nanoscrolls. https://doi.org/10.1088/2053-1583%2Fade9d8

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