In situ work function measurements of W, WO3 nanostructured surfaces

Surface nanostructuring enables the fabrication of materials with highly desirable properties. Nanostructured tungsten surfaces have potential applications in solar water splitting. Exposing a polished surface to helium plasma induces various morphological changes. Depending on ion energy, temperature, and fluence, clusters, bubbles foam-like nanostructures develop surface. In this study, were formed and/or oxidised, then examined using X-ray ultraviolet photoelectron spectroscopy (XPS UPS) without breaking vacuum. The chemical state nanostructured W or WO3 was not modified comparison pristine one. However, measuring line width emitted electrons from onset secondary up Fermi edge subtracting value incident photon work function acquired situ by UPS for increased 0.9 eV Helium ions effectively eliminated field emission sites via sputtering/implantation thereby function. No change measured WO3-pristine its fuzz: oxidation hindered effect helium. contrast W-fuzz sample, no identified WO3-fuzz, as diffused out during oxidation.