Evidence of the Existence of Three Types of Species at the Quartz−Aqueous Solution Interface at pH 0−10: XPS Surface Group Quantification and Surface Complexation Modeling

摘要: The surface composition of a quartz reacted with various aqueous solutions pH 0−10 was qualitatively and quantitatively evaluated using X-ray photoelectron spectroscopy (XPS). positions intensities the recorded Si 2p O 1s lines change depending on solution conditions. line, where position varies more significantly, analyzed in detail showing three components corresponding to species:  >SiOH2+, >SiOH0, >SiO- (where > represents bulk quartz). changes spectra support these findings. atomic ratio between oxygen silicon atoms found be 1.8. These data allow proposing two-step deprotonation model two are bonded one atom most deprotonated sites show SiO- configuration. Physisorbed water amount around 10% monolayer also all samples under spectroscopic investigation. density th...