Abstract
The electrochemical behavior of 
, and 
melts was studied in argon and 
/air atmospheres using a gold electrode. In order to identify the voltammetric waves due to 
, molten 
and mixtures of 
were investigated by voltammetry performed with Au and Pt electrodes in an argon atmosphere. It was shown that 
reduction took place at 0.26 V vs. an 
/Ag reference electrode, i.e., at a potential in between the V(V) → V(IV) and V(IV) → V(III) reduction stages. The presence of 
caused an increased concentration of V(III) species in the 
containing molten electrolytes. This effect may be caused either by protonic promotion of the V(IV) → V(III) reduction 
or by chemical reduction of V(IV) complexes with hydrogen, formed from 
as the product of the electrochemical reduction. Both the V(V) → V(IV) reduction and the V(IV) → V(V) oxidation remained one‐electron electrochemical reactions after the addition of 
(or water) to the 
melt. Water had no noticeable effect on the V(V) → V(IV) reduction but the V(IV) → V(V) oxidation proceeded at higher polarizations in the water‐containing melts in both argon and 
/air atmospheres. This effect may be explained by participation of the water molecules in the V(IV) active complexes.