Automated Deconvolution and Quantification of Peak Overlaps in MoS2

Molybdenum disulfide (MoS₂) is an industrially important material since it is the primary ore for Molybdenum. It has a wide range of applications, e.g. as a dry lubricant in automotive and machining, as a catalyst in chemical industry and as an indirect bandgap material in semiconductor industry.
Deconvolution and quantification of materials with strong peak overlaps in EDS spectra has always been an analytical challenge. MoS₂ is one such material where the K-lines of Sulphur (S) strongly overlap with L-lines of Molybdenum (Mo). We used XFlash^® FlatQUAD, a special high-performance EDS detector from Bruker to acquire EDS point-spectra of MoS₂ as shown in Fig. 1. The spectra were deconvoluted and quantified using ESPRIT 2 analytical software from Bruker. ESPRIT's powerful deconvolution and fitting methods were able to correctly identify and fit the individual peak overlaps (Fig. 2, Fig. 3). The standard-less quantification of the spectra gave the atomic concentration of Mo and S very close to the stoichiometric concentration.