The Reaction of Germanium with Nitric Acid Solutions

Abstract

Above 6 to 8N, HNO3 , the initial dissolution rate of germanium decreased with increasing HNO3 concentration and increasing stirring rate. The time required to bring about passivation of the germanium in these solutions decreased from several hours to a few seconds in going to higher HNO3 concentrations. A surface oxide film (very likely GeO2 ) is associated with the passivity of germanium. Accordingly, the presence of HF which dissolves GeO2 but not germanium prevented germanium passivity. Dissolution potential measurements were consistent with the kinetic data.