NovelV(III) compound, V(OH)(HCOO)2 has been synthesized by controlled current electrolysis route. V(OH)(HCOO)2
precipitation during electrolysis was found to depend on both pH and
concentration of V(III) in solution. It is an ionic V(III) compound with
mild associated organic anion. The compound readily dissolves in pure
water but subsequently precipitates out as polymer depending upon
concentration and aging duration. However a stable aqueous solution with
significantly high V(III) concentration could be prepared from it by
adding a suitable complexing agent like nitrilotriacetic acid (NTA) and
citric acid. These complex formulations will have potential application
for nuclear power plant application and vanadium redox batteries.
Electrochemical evaluation of the reduction characteristics of the
compound on glassy carbon and stainless steel electrodes has established
the varying effect of free acid at these surfaces. Part consumption of
current for proton reduction on stainless steel electrodes and blocking
of active sites by H+ adsorption on carbon surfaces was
observed. Thus, a high surface area carbon based electrodes will be
better suited for high current efficiency during vanadous solution
preparation by electroreduction while stainless steel electrodes may be
used for efficient hydrogen generation from organic acids.