Evolution of spectroscopy features in layered MoSxSe(2-x)solid solutions

Alejandro Fajardo-Peralta, Minh An T. Nguyen, J. Valenzuela-Benavides, Alexander Brodie, Rafael Nunes Gontijo, Ana Laura Elías, Néstor Perea-Lopez, Thomas E. Mallouk, Mauricio Terrones

Research output: Contribution to journalArticlepeer-review


In this work we report the structural and spectroscopic characterization of the bulk MoSxSe2-x solid solutions synthesized by chemical vapor transport. The bulk crystals were analyzed by scanning electron microscopy (SEM), x-ray diffraction (XRD), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), x-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Electron microscopy evaluation of the layered materials shows two distinct types of crystals: flat and easily cleavable hexagonal microcrystals up to 50 μm in size, and agglomerated irregular crystals of 5-10 μm in size. XRD shows a consistent increase in interplanar spacing as the Se content is increased in the sample series. Raman spectra of bulk MoSxSe2-x obtained with three different excitation energies revealed first order phonon modes associated with pure MoS2 (x = 2) and MoSe2 (x = 0) along with a complex behavior of vibrational modes when x had intermediate values. XPS Mo3d line scans indicate a slight shift towards lower binding energies as the Se/S ratio increases, consistent with the expected energies of MoSe2. A simple and direct relationship can be established between the characteristic Raman peaks and the value of x, which can be useful for identifying the compositions of TMD crystals.

Original languageEnglish (US)
Article number046301
JournalMaterials Research Express
Issue number4
StatePublished - Apr 2022

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Surfaces, Coatings and Films
  • Polymers and Plastics
  • Metals and Alloys


Dive into the research topics of 'Evolution of spectroscopy features in layered MoSxSe(2-x)solid solutions'. Together they form a unique fingerprint.

Cite this