The Electrochemical Behavior of Zr(Ⅳ) and Y(Ⅲ) in NaCl-KCl-K2ZrF6-YCl3 Molten Salt

Abstract The electrochemical behavior of Zr(Ⅳ) and Y(Ⅲ) in NaCl-KCl-K2ZrF6-YCl3 molten salts was studied by cyclic voltammetry, linear sweep voltammetry, and chronopotentiometry methods, which provides a theoretical foundation for the preparation of Zr-Y alloy coating by molten salt electrodeposition method. Results show that the reduction of Zr(IV) on molybdenum electrode is a three-step charge-transfer process, while the reduction of Y(III) is a single-step diffusion-controlled three-electron quasi-reversible process at -0.30 V vs. Pt. In addition, the diffusion coefficient of Y(III) in the melt at 750°C is calculated as 2.15×10-5 cm2·s-1. The reduction of Zr(IV) and Y(III) on molybdenum electrode in NaCl-KCl-K2ZrF6-YCl3 molten salts has also been studied by cyclic voltammetry method. Results indicate that the Zr-Y alloy coating can be obtained on molybdenum electrode by galvanostatic electrolysis at -1.50 V vs. Pt for 30 min.