Abstract
electrodes supported on Ni were prepared by thermal decomposition of mixtures of the nitrates at 400°C in the composition range from 0 to 20 mole percent 
. The surface morphology was observed on the scanning electron microscope, while the surface composition was determined by x‐ray photoelectron spectroscopy. Electrochemical characterization in 
solutions included voltammetric curves at different pH and different potential scan rates, as well as with different negative potential limits and different times of cathodic polarization. Electrochemical and nonelectrochemical data converge to indicate low porosity and low surface area at low 
contents, while the opposite is the case at high
concentrations. The surface is remarkably enriched with 
. Cathodic polarization degrades the spinel structure. There is some evidence that 
may retard the reduction of 
.