Charge Transfer Mechanism in Type II WO₃/Cu₂O Heterostructure

In this study, we explore the charge transfer mechanism between WO₃ and Cu₂O in heterostructured WO₃/Cu₂O electrodes and in a WO₃||Cu₂O tandem photoelectrochemical cell. The physical-chemical characterizations of the individual WO₃ and Cu₂O electrodes and the heterostructured WO₃/Cu₂O electrode by XRD, XPS, and SEM methods confirm the successful formation of the target systems. The results of photoelectrochemical studies infer that in both the heterostructured WO₃/Cu₂O electrode and WO₃||Cu₂O tandem photoelectrochemical cell, the major mechanism of charge transfer between WO₃ and Cu₂O is a realization of the Z-scheme.