Cu 2 O is a promising earth-abundant semiconductor photocathode for sunlight-driven water splitting. Characterization results are presented to show how the photocurrent density (J ph), onset potential (E onset), band edges, carrier density (N A), and interfacial charge transfer resistance (R ct) are affected by the morphology and method used to deposit Cu 2 O on a copper foil. Mesoscopic and planar morphologies exhibit large differences in the values of N A and R ct. However, these differences are not observed to translate to other photocatalytic properties of Cu 2 O. Mesoscopic and planar morphologies exhibit similar bandgap (eg) and flat band potential (E fb) values of 1.93±0.04 eV and 0.48±0.06 eV respectively. E onset of 0.48±0.04 eV obtained for these systems is close to the E fb indicating negligible water reduction overpotential. Electrochemically deposited planar Cu 2 O provides the highest photocurrent density of 5.0 mA cm− 2 at 0 V vs reversible hydrogen electrode (RHE) of all the morphologies studied. The photocurrent densities observed in this study are among the highest reported values for bare Cu 2 O photocathodes.