ALLOY FORMATION DURING THE CATHODIC POLARIZATION OF SOLID TELLURIUM IN MOLTEN-SALTS

Alloy formation during cathodic polarization of tellurium in LiNO//3-LiNO//2-LiOH and LiNO//3-KNO//3 melts at 423 degree K and in LiF-LiCl-LiI and LiCl-KCl melts at 650 degree K is investigated. The investigation was carried out by taking polarization curves in the potentiodynamic and pulse galvanostatic modes. Three waves are found on the polarization curve taken in the potentiodynamic mode at a tellurium cathode in molten LiNO//3-LiNO//2-LiOH. Waves II and III are related to the discharge of lithium ions on the cathode, with the formation of the heterogeneous alloys Te plus LiTe//3 and LiTe//3 plus Li//2Te on the electrode surface. Reverse polarization at the potentials of the third wave leads to the appearance of two waves on the anodic curve. They are caused by the electrochemical dissolution of lithium from the heterogeneous alloys.