Abstract
Recent studies by Savadogo et al. and Kulesza et al. indicated that 
is an active support for the reduction of oxygen on a 
electrode in phosphoric and sulfuric acid. However, the mechanism involved is not clear. 
is slightly soluble in acidic media. The addition of 
of dissolved tungsten in sulfuric acid at 
results in a 60% increase in oxygen reduction at a current density at 
vs. standard hydrogen electrode on a Teflon bonded 
electrode 
. A homogeneous 
decomposition mechanism involving the electrochemical reduction of dissolved peroxytungstate and its subsequent reoxidation by 
is proposed. ©1999 The Electrochemical Society