The Au NPs are readily active catalysts for the EOR. As illustrated in Figure , the typical cyclic voltammogram (CV) of the EOR catalysed by Au NPs is obtained for all samples, see details in Figure . In the forward scan, from low to high potentials, a significant increase in current is observed around 1.1-1.2 VRHE. This corresponds to the oxidation of the alcohol to retrieve in theory up to 12 electrons to lead to CO2, although in most cases many intermediates are formed and the oxidation is rarely complete . At too high potentials, the catalytic reaction is suppressed by the formation of Au-oxides . In the backward scan, from low to high potentials, a second oxidation peak is observed, of lower intensity