Influence of oxidation-Reduction conditions of synthesis on oxidation states of Cr, Mo, and Co Ions in high-silica glasses

Abstract

Investigations of porous high-silica glasses treated by aqueous solutions of Cr, Mo, and Co salts and subjected to thermal treatment in air and vacuum have been carried out. The results have been analyzed using EPR spectra and electron absorption spectra. The influence of the oxidation-reduction conditions of synthesis of high-silica glasses on the oxidation states of ions introduced into the glass has been demonstrated. It has been shown that chromium ions are strongly affected by the ambient environment and that their introduction into the glass structure is accompanied by a change in the oxidation state; this effect is less pronounced for molybdenum, and cobalt ions are most stable.