冶金工程学院

Nanoscience and Nanotechnology Letters

中文关键字：惰性电极;电化学;熔盐电解;阴极;碱金属，英文关键字：Inert Electrode;Electrochemistry;Molten-Salt Elect

Cyclic voltammetry and line scanning of the cross section was employed to study electrochemical and electrode behaviors of K and Na alkali metals in different types of electrolyte melts under polarization condition. The penetrative and migratory behaviors for the K and Na metals in TiB2–C composite cathode were also discussed. A self-made modified Rapoport apparatus was used to test the electrolysis expansion for the TiB2–C composite cathode and the diffusion coefficient for the K and Na metals was also calculated. The results showed that, in the mixed electrolyte melts of potassium cryolite and sodium cryolite, K and Na alkali metals combined with Al will precipitated together, and the Na precipitation was easier than that of K. The obtained alkali metals penetrated into the cathode and formed the corresponding C–K/C–Na intercalation compounds. The stability for the C–K intercalation compounds was better and collapsing force for K was stronger than that of Na. The penetrative and migratory path for the alkali metals under the polarization conditions was as follows; pore of cathode→binder coke→carbonaceous aggregates. The penetrative ability for K was stronger than that of Na. However, the K and Na could still not penetrate into the TiB2. The K and Na metals penetration into the binder coke and carbonaceous aggregates led to the electrolysis expansion of cathode which achieved maximum value when the concentration of the alkali metals in the cathode was saturated. The addition of potassium cryolite induced the increase of electrolysis expansion but did not have effect on the diffusion coefficient of alkali metals in the cathode. The diffusion coefficient had nothing to do with the composition of the electrolyte, which was only influenced by temperature. The higher the temperature in the cathode, the larger the diffusion coefficient for the alkali metal was and the more severe the corrosion of the cathode will be.

SCI检索

高娜,刘庆生

liumanbo,lixiaoming,fangzhao

Journal paper

卷：8

期：6

页：484-494

no

2016-08-01