ZrO2-and HfO2-based electrochemical sensors intended for investigation of glass-forming oxide melts

A theoretical analysis was made of the possible use of solid electrolytes with oxygen-ion conductivity for investigation of the relative basicity of silicate melts, and the optimum design of the electrochemical cell was chosen. Glasses in the SiO₂-Na₂O system were synthesized, and ceramic sensory membranes based on the cubic solid solution (ZrO₂)_0.92(Y₂O₃)_0.08 were prepared. An electrochemical cell based on ZrO₂ and HfO₂ and intended for investigation of glass-forming melts with the use of a platinum electrode and a reference electrode with oxygen-ion conductivity was designed and fabricated. The concentration dependence of the electromotive force of the electrochemical cells was examined for melts in the SiO₂-Na₂O system containing alkali oxide in different concentrations. A mathematical treatment of the obtained dependence of the electromotive force on the Na₂O concentration in this system was performed. The results obtained were used to calculate the relative oxygen ion activities and the corresponding pO values for alkali silicate melts under investigation.