期刊论文

中文

核化学与放射化学

0253-9950

2022

44

2

192-199

10.7538/hhx.2022.YX.2021052

国家自然科学基金资助项目（No.21790373）； 国家***科学基金资助项目（No.21925603）；

本校为第一机构

在LiCl-KCl共晶盐中,研究了在不同温度下La~(3+)的反应动力学机理。首先,在723~873K范围内,利用循环伏安法(CV)测得La~(3+)的扩散系数D为3.06×10~(-5)~6.08×10~(-5) cm~2/s,并根据Arrhenius方程计算了La~(3+)在电解质中的扩散活化能E_D=34.51kJ/mol。随后,利用电化学阻抗谱技术(EIS)研究了La~(3+)在电极上的动力学参数并测得交换电流密度i_0为0.48~1.39A/cm~2、反应速率常数k0=2.04×10~(-4)~5.90×10~(-4) cm/s及反应活化能E_a=35.04kJ/mol。通过Nyquist图和拟合的等效电路图研究La~(3+)在W电极上的反应动力学机理,发现在LiCl-KCl共晶盐中La~(3+)的电化学反应速率不仅受扩散控制还受电荷转移...

In this paper, the reaction kinetic mechanism of La3+ was studied in the LiCl-KCl eutectic salt at various temperatures. First, the diffusion coefficient of La3+(D) measured by cyclic voltammetry(CV) increases from 3.06×10-5 cm2/s to 6.08×10-5 cm2/s with the temperature ranging from 723 K to 873 K, and the activation energy of La3+ diffusion(ED) in the molten salts is 34.51 kJ/mol calculated by the Arrhenius equation. Subsequently, the kinetic parameters of La3+ on the W electrode were studied by the electrochemical impedance spectroscopy(EIS...