Electrodeposition of tungsten coating as plasma facing materials for fusion reactor

Tungsten coating has been electrodeposited form Na₂WO₄-ZnO-WO₃ molten salts in an open air condition. The electro-chemical mechanism of tungsten in such molten salts has been studied by cyclic voltametry and chronoamperometryt. It has been found that a cathode reduction peak appears at a potential of about 700 micro-volt (vs platinum quasi-reference electrode) and the outcome of iso potential electrolysis at the same potential proved to be metallic tungsten by XRD. The electro-deposition of tungsten in such molten salts are regarded as one-step six electron reduction process. Electro-crystallization process is a progressive nucleus formation process.