One-step hydrothermal synthesis of a porous Cu2O film and its photoelectrochemical properties.

A cuprous oxide (Cu2O) film with a novel porous structure is successfully synthesized on Cu foil by using a simple hydrothermal method. A redox reaction occurs between Cu and Cu2+ in aqueous solution to form the Cu2O film. The porous structures are formed as a result of the Ostwald ripening mechanism. In addition, photoluminescence measurements indicate that the porous Cu2O film may reduce the recombination of photogenerated electrons and holes. The UV/Vis absorption property of the porous Cu2O film is better than that of the granular Cu2O film, and its high photocurrent is expected to make the porous Cu2O film more suitable for solar energy applications.