Invention:
This invention is a new reference electrode that was prepared by anodizing (electrochemically oxidizing) silver metal in a sodium sulfide solution (SSSE). This results in a silver metal wire coated with silver sulfide. The electrode is extremely stable. The measured potentials for SSSE versus SSCE during two experiments in 1 molar KCl in air were 0.883 and 0.886V. The test for SSSE versus SSCE run in NaCl-KCl molten salt at 800C against the high temperature SSCE was measured at 0.866V. The invention is also capable of operating at lower temperatures than typical reference electrodes, including as low as room temperature.
Background:
A reference electrode can measure the voltage potential of a material or liquid in a pipe. Typically, they are difficult to use with temperatures which are under 800C. A reference electrode, when used in conjunction with other corrosion prevention techniques, can help eliminate oxidation of the pipes, tanks, etc. which carry corrosive material. The typical reference electrode consists of an internal element, normally silver-silver chloride, surrounded by an electrolyte-containing filling solution (commonly KCl, saturated with AgCl) which is contained in either a glass or plastic body salt bridge, which terminates at the liquid junction. It is important that the internal element remain wet and surrounded by the reference electrolyte filling solution.
Applications:
- Corrosion sensor and control
- Control of metal refining
- Measure the voltage potential of a material or liquid in a pipe
- Fuel cells
Advantages:
- Extremely stable as a reference electrode
- It is simple and effective to use in sensors and control devices
- It can be used in temperatures as high as 800C or more, depending on the solvents used
