Sulfur

The predominant photoemission for sulfur is the 2p region, which consists of a doublet with a reasonable doublet separation (1.16 eV – Figure 1). This region may overlap with Bi 4f and Se 3p.

Figure 1: S 2p spectra of S8(1)

Since binding energy shifts may be small for organic sulfurs and polysulfides, the S 2p:KLL auger parameter may make state identification simpler.(1)

Si 2s plasmons can overlap with the S 2p region and render appropriate background simulation difficult in the cases of low S:Si ratio.

Typical binding energies for sulfur compounds may be found in table 1.

Species Si 2p3/2 Binding energy / eV Charge ref Ref
S8 164.3 N/A 2
Li2S 160.8 N/A 3
Thiol, R-SH 162 C 1s / 284.6 eV 4
Thiol, Au-SH 162.8 Au 4f / 84 eV 5
Sulfonic acid (R-SO3H) ~168 C 1s / 284.8 eV 6
Sulfated zirconia 169.2 C 1s / 284.6 eV 7
CuSO4 168.8 C 1s / 284.6 eV 8
Table 1: Typical sulfur 2p binding energies

References

  1. Spectra recorded by HarwellXPS
  2. Fantauzzi, M., et al. (2014). “A contribution to the surface characterization of alkali metal sulfates.” Journal of Electron Spectroscopy and Related Phenomena 193: 6-15. Read it online here.
  3. Fantauzzi, M., et al. (2015). “Exploiting XPS for the identification of sulfides and polysulfides.” RSC advances 5(93): 75953-75963. Read it online here.
  4. Wilson, K., et al. (2002). “Structure and reactivity of sol–gel sulphonic acid silicas.” Applied Catalysis A: General 228(1-2): 127-133. Read it online here.
  5. Sun, S., et al. (2006). “Fabrication of gold micro-and nanostructures by photolithographic exposure of thiol-stabilized gold nanoparticles.” Nano letters 6(3): 345-350. Read it online here.
  6. Isaacs, M. A., et al. (2019). “Unravelling mass transport in hierarchically porous catalysts.” Journal of Materials Chemistry A 7(19): 11814-11825. Read it online here.
  7. Rabee, A. I., et al. (2017). “Acidity-reactivity relationships in catalytic esterification over ammonium sulfate-derived sulfated zirconia.” Catalysts 7(7): 204. Read it online here.
  8. Vasquez, R. (1998). “CuSO4 by XPS.” Surface Science Spectra 5(4): 279-284. Read it online here.
Created: May 14, 2024