Although hybrid CuO:Zn has a small bandgap energy similar to that of pristine CuO and a relatively high photocurrent, it suffers from photocorrosion. Herein, we report the electrodeposition of CuO:Zn nanostructures in which the photoelectrochemical properties are governed by the twisting of the coordination sphere or the Fermi level pinning of Zn ions. We extended the absorption range to the visible region while doubling its apparent photocurrent compared to that of CuO. The implementation of Zn ions enlarged the space-charge region, thus triggering electron availability for the photolysis of water, which is unusual for p-type semiconductors. Moreover, the excellent crystallinity, high surface area, and adhesion to the FTO (Fluorine-doped Tin Oxide) glass remarkably improved the photocatalytic activity of the CuO:Zn thin film with a cathodic photocurrent of -4 mA/cm2 and a quantum efficiency of 35%, making it a promising candidate for hydrogen production.