Photoelectron spectroscopic study of the interaction of thin Fe films with the MoS2(0001) surface

Abstract The Fe/MoS 2 (0001) interface has been studied by high-resolution photoelectron spectroscopy using synchrotron radiation. The evolution of the Mo3d, Fe3p, and S2p core levels and of the valence band spectra ( hν = 152 eV ) during growth of vapor-deposited Fe films (1–10 A) indicates the production of sulfur vacancy defects in the MoS 2 (0001) surface. Several submonolayer sulfur surface species were formed, including sulfur adsorbed on the Fe surface and a reacted Fe-S species. The MoS 2 surface was found to be covered for Fe film thicknesses of ~10 A. Annealing a 10 A film to 600 K resulted in the Fe film beginning to agglomerate, while annealing to 700–900 K resulted in further agglomeration of the Fe film. Annealing to 700–900 K also resulted in reformation of a partially disordered MoS 2 (0001)-1 × 1 surface with ~5% defects, as determined from photoelectron spectroscopy and low-energy electron diffraction. The overlayer film remained primarily in the form of metallic Fe, before and after annealing to temperatures ≲ 900 K, which was shown by the behavior of the Fe3p core level spectra and valence band spectra. Annealing the sample to 1200 K resulted in decomposition of the MoS 2 (0001) surface. The results indicate that the Fe/MoS 2 (0001) system exhibits some interfacial reactivity but does not form bulk Fe-S compounds. The results have been compared to those of previous studies of the Fe/MoS 2 (0001) system.