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.