Raman Spectral Characteristics and Vibrational Mechanism Analysis of Layered Molybdenum Disulfide

ABSTRACT Molybdenum disulfide (MoS 2 ), a prototypical semiconductor of the transition metal dichalcogenide (TMD) family, finds extensive applications in various fields such as optical sensing, electronics, photocatalysis, and flexible substrates. When subjected to long‐term storage or improper preservation, MoS 2 may undergo oxidation, adsorption of contaminants, structural degradation, or interlayer re‐agglomeration, which can significantly compromise its performance. This study employs experimental detection via Raman spectroscopy, supplemented by computational analysis using the quantum chemistry simulation software Gaussian 16W. Firstly, three experimental samples are analyzed using a Raman spectrometer. Secondly, the cluster structures of monolayer, 2H‐phase, and 1T‐phase layered MoS 2 are modelled and computed using Gaussian 16W. Finally, spectral characteristics and vibrational mechanisms are analyzed. Experimental results indicate that when structural damage occurs in MoS 2 , its characteristic peak near 411 cm −1 exhibits an increased FWHM, peak splitting, and a gradual blue shift, accompanied by peak broadening in the low‐wavenumber region. Theoretical calculations reveal that these spectral evolution features originate from changes in the interlayer stacking modes and an increase in lattice disorder within MoS 2 . This work provides a new criterion for the non‐destructive and rapid monitoring of the layer count in MoS 2 , and also offers valuable insights for the Raman spectroscopic detection of structural damage in other layered materials.