Charge separation at the modified surface of cuprous oxide thin film

Photocurrent improvement for the photoelectrochemical cell, based on a Cu2O/Cu electrode in hydrophobic ionic liquid electrolyte, was demonstrated by modifying the Cu2O surface using cyanide treatment, in this case the photocurrent amplitude drastically increased at least by a factor of 10 compared with the non-treatment. Passivation of the surface defect sites through the cyanide treatment process resulted in significantly raising the charge separation yield at the interface. From this experimentation the optimization of the cyanide treatment and the limitation of the photocurrent are considered.