Fabrication of Cu2O/Si nanowires photocathode and its photoelectrochemical properties.

Using a simple dipping method, Cu₂O nanoparticles were successfully deposited on the surface and the sidewall of silicon nanowires (Si NWs). As a photocathode, the Cu₂O/Si NWs composites not only show a low reflectance of 10.75% in the 300–900 nm wavelength range, but also can enhance the separation of the photogenerated electron–hole pairs due to the junction formed by Cu₂O and Si NWs. The Cu₂O/Si NWs-20 min photocathode achieved a photocurrent of 3.5 mA cm⁻² at −0.8 V versus AgCl/Ag and a photoconversion efficiency of 1.2%. [ABSTRACT FROM AUTHOR]