CuO and Cu2O nanostructures: pathway to efficient dark current density

This study investigates the fabrication of CuO and Cu2O nanostructures by a simple solution-based method followed by thermal annealing. Pure CuO was obtained at 180 degrees C, while higher temperatures yielded Cu2O/CuO heterostructures. The pure CuO film exhibited the highest photocurrent density (140.05 mA/cm(2)) and a notable dark current density (60.27 mA/cm(2)). Although the heterostructures showed lower photocurrents, they also demonstrated significant dark currents (9.03-16.27 mA/cm(2)) across different annealing temperatures. These findings suggest a promising approach for developing effective CuO-based photoelectrodes with both excellent photocatalytic capabilities and a potential for dark current generation.