In situ ambient pressure X-ray photoelectron spectroscopy (APPES) and scanning force microscopy were used to characterize the surface discharge induced by water layers grown on (001) surfaces of sodium chloride single crystals. The APPES studies show that both kinetic energy (KE) and full width at half-maximum (FWHM) of the Na 2s and Cl 2p core level peaks, monitored as a function of relative humidity (RH), mimic surface conductivity curves measured using scanning force microscopy. The KE position and FWHM of the core level peaks therefore are directly related to the solvation and diffusion of ions at the NaCl(100) surface upon adsorption of water. © 2008 American Chemical Society.
Verdaguer, A., Segura, J. J., Fraxedas, J., Bluhm, H., & Salmeron, M. (2008). Correlation between charge state of insulating NaCl surfaces and ionic mobility induced by water adsorption: A combined ambient pressure X-ray photoelectron spectroscopy and scanning force microscopy study. Journal of Physical Chemistry C, 112(43), 16898-16901. https://doi.org/10.1021/jp805444v