Zinc ferrite-based p-n homojunction with multi-effect for efficient photoelectrochemical water splitting

A novel one-dimensional core-shell zinc ferrite (ZnFe₂O₄) p-n homojunction is prepared by a facile two-step hydrothermal method. The core-shell homojunction is constructed by decorating p-type Ni-ZnFe₂O₄ (shell) onto n-type ZnFe₂O₄ (core). As expected, significant enhancement in the photocurrent density of the developed homojunction is realized compared to that of pristine ZnFe₂O₄ (6.64 times that of pristine ZnFe₂O₄). This improvement is ascribed to the fact that the ZnFe₂O₄ homojunction has multiple optimization effects, namely, a built-in electric field and active sites on Ni-ZnFe₂O₄, which are beneficial to carrier separation and transport. This study paves a promising pathway for the use of ion doping to design high-quality p-n homojunctions with multiple effects for enhancing charge separation in the photoelectrochemical water splitting configuration.