Garg, SouravFix, J. PierceKrayev, Andrey V.Flanery, ConnorColgrove, MichaelSulkanen, Audrey R.Wang, MinyuanLiu, Gang-YuBorys, Nicholas J.Kung, Patrick2022-09-162022-09-162022-01Garg, Sourav, J. Pierce Fix, Andrey V. Krayev, Connor Flanery, Michael Colgrove, Audrey R. Sulkanen, Minyuan Wang, Gang-Yu Liu, Nicholas J. Borys, and Patrick Kung. "Nanoscale Raman Characterization of a 2D Semiconductor Lateral Heterostructure Interface." ACS nano 16, no. 1 (2021): 340-350.1936-0851https://scholarworks.montana.edu/handle/1/17168This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in ACS Nano, copyright © American Chemical Society after peer review. To access the final edited and published work see https://doi.org/10.1021/acsnano.1c06595The nature of the interface in lateral heterostructures of 2D monolayer semiconductors including its composition, size, and heterogeneity critically impacts the functionalities it engenders on the 2D system for next-generation optoelectronics. Here, we use tip-enhanced Raman scattering (TERS) to characterize the interface in a single-layer MoS2/WS2 lateral heterostructure with a spatial resolution of 50 nm. Resonant and nonresonant TERS spectroscopies reveal that the interface is alloyed with a size that varies over an order of magnitude─from 50 to 600 nm─within a single crystallite. Nanoscale imaging of the continuous interfacial evolution of the resonant and nonresonant Raman spectra enables the deconvolution of defect activation, resonant enhancement, and material composition for several vibrational modes in single-layer MoS2, MoxW1–xS2, and WS2. The results demonstrate the capabilities of nanoscale TERS spectroscopy to elucidate macroscopic structure–property relationships in 2D materials and to characterize lateral interfaces of 2D systems on length scales that are imperative for devices.en-UScopyright American Chemical Society 2022TERSraman2D lateral heterostructureinterface2D alloysArticle