Understanding the electrochemical hydrogenation of acetone on Pt single crystal electrodes

Abstract

The heterogeneous upgrading of biomass by means of electrocatalytic hydrogenation is an attractive way to refine products for industrial and pharmaceutical purposes. Also, the efficient electrochemical reduction of carbonyl compounds can act as hydrogen vectors, and therefore energy vectors. In this manuscript, we render further fundamental insights into the electrochemical reduction of acetone as a model molecule of carbonyl compounds. The structural sensitivity of the reaction is demonstrated by using platinum single crystal electrodes with low Miller indices and stepped electrodes with (110) terraces and either (111) or (100) monoatomic steps. Among the basal planes, Pt(110) is the only one active for the electroreduction of acetone. The inclusion of (111) steps on the (110) terraces does not significantly alter the behavior of Pt(110), but increasing the (100) step density has been observed to decrease the activity. We attribute this different performance to a geometrical effect of the active sites. By using different supporting electrolytes, we have found that sulfate competes with acetone for the surface sites, thus modifying the adlayer interfacial structure and hampering acetone reactivity.