Investigation of high temperature reactions on graphite with Rutherford backscattering spectrometry: interaction of cadmium, lead and silver with a phosphate modifier

Abstract

The depth-dependent concentration profiles of nitrate salts of Pb, Cd and Ag were observed with and without the addition of (NH₄)H₂PO₄ chemical modifier using Rutherford backscattering spectrometry (RBS). The RBS results demonstrate that the analytes, in all the systems investigated, readily migrate (≥3 µm) into the pyrolytic graphite coated graphite substrate at room temperature. The stabilization of Cd and Pb with the phosphate modifier is proposed to be due to the formation of a phosphate glass. Silver did not extensively interact with the phosphate modifier and was, as a result, not stabilized.