Surface modification of a silicate glass during XPS experiments

Abstract

The surface chemistry of a commercial soda-lime silicate glass is shown to change during a long-duration XPS experiment wherein the glass surface was exposed to the monochromatic x-rays and low-energy electrons (0.2-5 eV) that compensate for the charging of the surface. The atomic percentage of sodium increases and that of oxygen decreases with increasing time of the experiment. The separate influence of x-rays and the low-energy electrons on the glass surface is also measured. The results show that diffusion of the sodium ions is enhanced more in the presence of x-rays than in the presence of low-energy electrons. All observations can be explained well by a model that considers the breaking of the bridging and non-bridging oxygen bonds, and the trapping of photoelectrons and the externally supplied electrons. Although long-duration XPS experiments show significant changes on the exposed surface, the chemical composition of the bulk glass obtained during a short experiment agrees well with that obtained from the chemical analysis.

Effect of chemical structure of organics on pore wetting

“…The composition of adventitious C was not involved in the XPS surface chemical composition analysis. In addition, our data is similar with the XPS data reported in literature for cleaned soda-lime silicate glass surface (Sharma et al, 2001). Thus, we can conclude that the glass capillary inner surface is no significant measurable chemical contamination.…”

Potassium surface enrichment in mixed alkali glass irradiated with electrons

“…The detection angles were 0°and 60°counted from the surface normal. Although some changes introduced by X-rays in glass are reported [18,19], our exposure conditions were very mild: non-focused beam, low source power, and low-photon density were used to eliminate the influence of X-ray irradiation during spectra recording. It needs to be underlined that no electron flooding was used during spectra recordings.…”

Light-induced atom desorption from glass surfaces characterized by X-ray photoelectron spectroscopy

“…This ion exchange can probably cause the chemical shift of Na. It was not obvious whether the increase in the Na 1s peak was caused by Rb deposition, because a long-duration XPS experiment indicated an increase in Na concentration on a soda lime silicate glass surface [23].…”

“…To obtain XPS spectra, which are photoelectron intensities as a function of the binding energy, we used an AlKα X-ray (1486.6 eV). We calibrated the binding energies by adjustment of the Si 2p peak to 103.5 eV for SiO 2 , because the binding energy of silicon has been reported to be least dependent on the composition of silicate glass [23,24]. We removed baselines from the spectra using the Shirley method [25] and fitted them with Voigt functions to investigate the chemical bonding states of elements composing the surfaces.…”