Electrochemical deposition was employed to fabricate Cu 2 O nanocubes on indium-tin-oxide (ITO)-coated glass substrates at 75°C without using any template, catalyst, or seed layer. Scanning electron microscopy images showed that the Cu 2 O nanocubes with a nanoscale size were uniformly formed on ITO-coated glass substrates. X-ray patterns of the Cu 2 O nanocubes exhibited the dominant peaks corresponding to the Cu 2 O cubic structures. The current–voltage curves of an Au/n-type Al-doped ZnO/p-type Cu 2 O nanocube/ITO device clearly showed current rectifying behavior with a turn-on voltage of 3.6V.