(中山大學化學與化學工程學院物理化學研究所， 廣州 510275)
摘 要: 利用線性掃描伏安法研究了Yb(Ⅲ)在等摩爾NaCl-KCl熔體中Cu電極上還原的電化學行為及擴散系數。結果表明: Yb(Ⅲ)第一步可逆還原為Yb(Ⅱ)，Yb(Ⅱ)進一步還原并與Cu形成合金： Yb3++e=Yb2+, Yb2++2e+nCu=YbCun。 測定了Yb(Ⅲ)和Yb(Ⅱ)在973K NaCl-KCl熔體中的擴散系數分別為1.5×10-5和1.0×10-5 cm2s-1。用自耗陰極法在1123K, 陰極電流密度20 Acm-2, KCl-YbCl3(30%)熔體中制取了YbCu合金。
關鍵字: 鐿離子 Yb-Cu合金 電還原 熔鹽 制備
（Institute of Physical Chemistry, School of Chemistry and Chemical Engineering,
Zhongshan University, Guangzhou 510275, P. R. China）
Abstract:Linear sweep voltammetry has been used to study the redox of Yb(Ⅲ) in equimolar NaCl-KCl melt on the Cu cathode. It is reasonable to presume that the reduction of Yb(Ⅲ) to Yb(Ⅱ) is reversible on Cu electrode at first step and Yb(Ⅱ) is reduced to form alloy with Cu on Cu electrode surface: Yb3++e=Yb2+, Yb2++2e+nCu=YbCun. The diffusion coefficients of Yb(Ⅲ) and Yb(Ⅱ) in NaCl-KCl melt at 973 K are 1.5×10-5 and 1.0×10-5 cm2·s-1, respectively. The Yb-Cu alloy was prepared by consumable cathode in molten chlorides. The Yb-Cu alloy contains about 15% of Yb.
Key words: Yb(Ⅲ) ion Yb-Cu alloy electroreduction molten salt preparation
