Investigation of anodic polarization of the Ag (Hg) / Ag4RbI5interface

The electrochemical behaviour of Ag(Hg)/Ag4RbI5 interface is investigateded by potentiostatic pulse method. It is found out, that the rate-determining step of electrode reaction is the electron transfer with the exchange current density of 68 mA cm-2 and the transfer coefficient of approximately 0,45. The order of electrochemical reaction of silver oxidizing is estimated from polarization investigations of silver amalgam with various concentration. From here it is deduced, that the quicksilver is ionized and is implanted in the electrolyte together with silver at anodic polarization: 15 Ag + 85 Hg - 100e = 15 Ag+ + 85 Hg+. From comparison of electrochemical behaviour of Ag (Hg)/Ag4RbI5 and Ag/Ag4RbI5 interfaces it is concluded, that the rate of anodic silver dissolution on Ag/Ag4RbI5 interface is limited by crystallization effects.