title: Energetics at the Surface of Photoelectrodes and Its Influence on the Photoelectrochemical Properties.
abstract: Photoelectrochemistry (PEC) holds potential as a direct route for solar energy storage. Its performance is governed by how efficiently photoexcited charges are separated and how fast the charges are transferred to the solution, both of which are highly sensitive to the photoelectrode surfaces near the electrolyte. While other aspects of a PEC system, such as the light-absorbing materials and the catalysts that facilitate charge transfer, have been extensively examined in the past, an underwhelming amount of attention has been paid to the energetics at the photoelectrode/electrolyte interface. The lack of understanding of this interface is an important reason why many photoelectrode materials fail to deliver the expected performance in harvesting solar energy in a PEC system. Using hematite (α-Fe2O3) as a material platform, we present in this Perspective how surface modifications can alter the energetics and the resulting consequences on the overall PEC performance. It has been shown that a detailed understanding of the photoelectrode/eletrolyte interfaces can contribute significantly to improving the performance of hematite, which enabled unassisted solar water splitting when combined with an amorphous Si photocathode.
authors.affiliation: Department of Chemistry, Merkert Chemistry Center, Boston College , 2609 Beacon Street, Chestnut Hill, Massachusetts 02467, United States.
authors.forename: James E
authors.initials: JE
authors.lastname: Thorne
authors.affiliation: Department of Chemistry, Merkert Chemistry Center, Boston College , 2609 Beacon Street, Chestnut Hill, Massachusetts 02467, United States.|Key Lab for Anisotropy and Texture of Materials (MoE), Northeastern University , Shenyang 110819, China.
authors.forename: Song
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Chemistry, Merkert Chemistry Center, Boston College , 2609 Beacon Street, Chestnut Hill, Massachusetts 02467, United States.
authors.forename: Chun
authors.initials: C
authors.lastname: Du
authors.affiliation: Key Lab for Anisotropy and Texture of Materials (MoE), Northeastern University , Shenyang 110819, China.
authors.forename: Gaowu
authors.initials: G
authors.lastname: Qin
authors.affiliation: Department of Chemistry, Merkert Chemistry Center, Boston College , 2609 Beacon Street, Chestnut Hill, Massachusetts 02467, United States.
authors.forename: Dunwei
authors.initials: D
authors.lastname: Wang