In this work nanostrutured copper oxides (CuxO) were prepared by ultrasound-assisted anodization of copper foils. These CuxO nanostructures were characterized morphologically and structurally by SEM and XRD, respectively. The bandgap value was determined by diffuse reflectance measurements. The electrochemical characterization included Mott Schottky plots and electrochemical techniques. From these measurements it was possible to establish that the formed phase corresponded to p-Cu2O. The best results in the cathodic photocurrent response for the system Cu|p-Cu2O|10 mM KI, 1 mM KI3 in 50 mM Na2B4O7 (pH 9.2) were obtained with oxides prepared at 75°C, 100V in ethylene glycol contained 5% wt H2O and 0.5 wt% NH4Cl.