Electrochemical Studies in Half Cell

Electrodes coated with nanostracturcd Pd catalysts are generally active for alcohol oxidation in alkaline media, but both the type of the support material and the co-presence of other metals or metal oxides can remarkably affect the catalytic performance in terms of activity and electrochemical stability. 

On the other hand, the Pd/MWCNT electrode is electrochemically stable only for the oxidation of ethanol as the oxidation reactions of methanol and glycerol are featured by a fast increase of the overpotential (Fig. 13). 

The degradation of the Pd/MWCNT electrode during methanol and glycerol oxidation has been ascribed to the formation of adsorbed Indeed, ethanol is selectively 

On a specnlative basis, it has been suggested that the large polarization of the Pd/MWCNT electrode during glycerol 

CO bonding to the active sites and difficult product desorption vide infra). In contrast, the peak current density of methanol oxidation decreases with the scan rate (Fig. 14c), even by increasing the concentration of MeOH from 10 to 20 wt%, in an attempt of magnifying the diffiision effects. Apparently, the diffusion of MeOH across the MWCNT support is veiy fast but the electrocatalyst is not sufficiently active and the peak current density decreases by increasing the scan rate. 

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