铝电极在LiNO3-KNO3熔盐中的电化学行为

采用循环伏安和恒电位电解法考察了铝电极在LiNO3-KNO3熔盐中的电化学行为. 实验结果表明, 在该熔盐中, 锂离子在铝电极上的电还原过程伴随着新生态的锂原子向电极内部的随后扩散步骤; 锂原子进入铝电极后与铝发生合金化, 形成β-LiAl合金和γ-LiAl合金; 锂离子在铝电极上的还原过程受还原态锂在铝基体内的扩散步骤控制. 循环伏安实验发现, 铝电极在该熔盐中的氧化和还原峰电流都先随循环次数增加而增大, 最后基本上趋于稳定. 这表明铝电极在该熔盐体系中具有较好的电化学稳定性.

Electrochemical Behavior of Aluminium Electrode in LiNO3-KNO3 Molten Salt

The electrochemical behavior of aluminium in LiNO3-KNO3 molten salt electrolyte was studied by means of cyclic voltammetry and potentiostatic electrolysis. It was shown that the electrochemical reduction of Li+ at the aluminium electrode was followed by the diffusion of the nascent Li atom formed at the electrode surface into aluminiummatrix; and the β-phase and γ-phase Li-Al alloys were formed by alloying of Li atomwith Al; the electrode process was controlled by the diffusion of Li atom into Al matrix. The cyclic voltammetric experiments showed that both reductive peak current and oxidative peak current increased firstly with the increase of cycles, and then reached to a constant value after certain cycles. This indicated that the aluminium electrode had good electrochemical stability in the LiNO3-KNO3 molten salt electrolyte.