Long-Term Stability of Mullite and Magnesia-encased Ag|Ag⁺ Reference Electrodes in Molten MgCl₂-KCl-NaCl

In this study, the stability of Ag|Ag + molten chloride reference electrodes was studied using mullite and magnesia tubes as electrode membrane materials in MgCl 2 -KCl-NaCl for continuous immersion up to 31 d. Two electrochemical methods were used characterize long-term performance at 500 °C an inert atmosphere a Mg rod working electrode: open circuit potential (OCP) onset Mg(II) reduction measured by cyclic voltammetry (CV). There only 3% difference between average OCP versus MgO electrodes. Potential drift higher (−1.34 mV d −1 ) than (0.22 ). But both rates very low compared data standard deviation, indicating that no significant us