title: Photoelectrochemical properties of nanomultiple CaFe2O4/ZnFe2O4 pn junction photoelectrodes.
abstract: Nanomultiple CaFe2O4/ZnFe2O4pn junctions are prepared by a pulsed laser deposition method to explore their photoelectrochemical properties as the photoelectrodes. It is demonstrated that the multiple-pn-junction structure is favorable to enhancing the photocurrent density and the onset potential of the photoelectrode. Furthermore, the 20-junction photoelectrode-based PEC cell yields a high open circuit photovoltage of up to 0.97 V, which is much higher than that for a single pn junction photoelectrode PEC cell that yields an open circuit photovoltage of 0.13 V. A multiple-junction band structure model is assumed to describe the behavior of the CaFe2O4/ZnFe2O4 multiple-junction photoelectrodes. It is suggested that the open circuit photovoltage is dominated by the number of pn junctions in a multiple-junction photoelectrode and the carrier transfer inside the photoelectrode is improved by narrowing the single-layer thickness. These findings provide a new approach to designing the multiple-junction structure to improve the PEC properties of the photoelectrodes.
authors: Environmental Remediation Materials Unit, Catalytic Materials Group, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, Japan.
authors: Junyu
authors: J
authors: Cao
authors: Juanjuan
authors: J
authors: Xing
authors: Yuanjian
authors: Y
authors: Zhang
authors: Hua
authors: H
authors: Tong
authors: Yingpu
authors: Y
authors: Bi
authors: Tetsuya
authors: T
authors: Kako
authors: Masaki
authors: M
authors: Takeguchi
authors: Jinhua
authors: J
authors: Ye