Etching behavior of Pb ion from PbO-B2O3-SiO2 glasses in HNO3 solution

Abstract

Quantitative studies on the dissolution of Pb in an acid solution were conducted to understand the etching mechanism in PbO-SiO2-B2O3 glasses. In this study, the etching was done on bulk glasses of a PbO-SiO2-B2O3 system with a HNO3 solution at 40 °C, and the surface structure of the glasses and ion dissolution behavior were analyzed using X-ray photoelectron spectroscopy (XPS), Raman spectrophotometer, and inductive coupled plasma spectrometry, respectively. The results showed that Pb (1.5–5.5 %) and B (0.8–3 %) ions are the major components etched. Small amounts of Si, Al, Ti, and Zr were detected in the etching solution. The analysis of O1s in the XPS peaks showed that the ratio of non-bridging oxygen (NBO) to bridging oxygen (BO) changed from 1:2.7 to 1:0.6 after leaching with the HNO3 solution. The Si-O-Pb and Si-O-Si bindings on the glass surface appeared to be a silicon-rich region where Si-O binding occurs after etching.