The study of electronic structure of molybdenum and tungsten trisulfides and their lithium intercalates by x-ray electron and x-ray emission and absorption spectroscopy

Multi‐Functional Layered WS2 Nanosheets for Enhancing the Performance of Lithium–Sulfur Batteries

“…Figure c shows the S 2p spectrum and the results of the deconvolution, revealing spectra corresponding to various valence states of sulfur; five sulfur environments were identified. For WS 3 and S 2p, the spectra show two partially overlapping doublets attributed to S 2− 2 pairs (on the high‐energy side) and to S 2− (on the low‐energy side) in 1:2 proportions as observed in a previous report . The singlet peak located at 164 eV was assigned to the S–S bond from elemental sulfur; the other two peaks between 169 and 170 eV are due to the presence of SO 2− 4 or SO 2− 3 , which were likely produced via the oxidation of sulfur during the hydrothermal reaction .…”

Effect of Particle Size on the HDS Activity of Molybdenum Sulfide

“…MoS 3 synthesized by acidification of ATTM [34] solution is also included. This sample was prepared in order to compare the corresponding binding energies with those of the precipitated nanoparticles before reaction since the binding energy values reported in the literature vary widely [37][38][39][40][41][42][43][44][45][46][47].…”

Amorphous nickel/cobalt tungsten sulfide electrocatalysts for high-efficiency hydrogen evolution reaction

“…Signals of W 4+ and W 5+ species are commonly observed from amorphous WS x and its derivatives [67], but the ratios of the contents are smaller in amorphous NiWS than crystalline WS x . The W 6+ peaks representing oxidation of W are more obvious in NiWS, as the precursor becomes more unstable after WS 4 2− interacts with Ni 2+ [48,67]. In the S 2p spectrum, the peaks at 162.47-162.75 and 161.37−161.65 eV correspond to the S 2p 1/2 and 2p 3/2 of S 2− ligand [38].…”

“…The W 4f spectra are fitted to several doublets including W 4+ 4f 5/2-7/2 , W 5+ 4f 5/2-7/2 , and W 6+ 4f 5/2-7/2 [44]. Signals of W 4+ and W 5+ species are commonly observed from amorphous WS x and its derivatives [67], but the ratios of the contents are smaller in amorphous NiWS than crystalline WS x . The W 6+ peaks representing oxidation of W are more obvious in NiWS, as the precursor becomes more unstable after WS 4 2− interacts with Ni 2+ [48,67].…”