Voltammetry offers a technique to measure the concentration of ions in high-temperature molten salts, which are used in nuclear fuel and the recycling of rare-earth metals. Accurate high-temperature electrochemical measurements, however, are difficult to obtain due to interactions between the electrode and other elements as well as difficulty determining the surface area of the working electrode.

A newly developed fused glass electrode contains a fixed area metal rod. This enables accurate determination of area-dependent electrochemical measurements such as cyclic voltammetry. This fixes the surface area of the interface between the electrode and the electrolyte to eliminate uncertainty regarding the surface area. The electrode can also detect impurities, monitor ions of interest, and provide feedback for process control and optimization in high-temperature molten salts.