Held, G.; Venturini, F.; Grinter, D.C.; Ferrer, P.; Arrigo, R.; Deacon, L.; Quevedo Garzon, W.; Roy, K.; Large, A.; Stephens, C.; Watts, A.; Larkin, P.; Hand, M.; Wang, H.; Pratt, L.; Mudd, J.J.; Richardson, T.; Patel, S.; Hillman, M.; Scott, S.: Ambient-pressure endstation of the Versatile Soft X-ray (VerSoX) beamline at Diamond Light Source. Journal of Synchrotron Radiation 27 (2020), p. 1153-1166
10.1107/s1600577520009157
Open Access Version
Abstract:
The ambient-pressure endstation and branchline of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source serves a very diverse user community studying heterogeneous catalysts, pharmaceuticals and biomaterials under realistic conditions, liquids and ices, and novel electronic, photonic and battery materials. The instrument facilitates studies of the near-surface chemical composition, electronic and geometric structure of a variety of samples using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy in the photon energy range from 170 eV to 2800 eV. The beamline provides a resolving power hν/Δ(hν) > 5000 at a photon flux > 1010 photons s−1 over most of its energy range. By operating the optical elements in a low-pressure oxygen atmosphere, carbon contamination can be almost completely eliminated, which makes the beamline particularly suitable for carbon K-edge NEXAFS. The endstation can be operated at pressures up to 100 mbar, whereby XPS can be routinely performed up to 30 mbar. A selection of typical data demonstrates the capability of the instrument to analyse details of the surface composition of solid samples under ambient-pressure conditions using XPS and NEXAFS. In addition, it offers a convenient way of analysing the gas phase through X-ray absorption spectroscopy. Short XPS spectra can be measured at a time scale of tens of seconds. The shortest data acquisition times for NEXAFS are around 0.5 s per data point.