Boosting Photoelectrochemical Water Oxidation of Hematite in Acidic Electrolytes by Surface State Modification
State-of-the-art water-oxidation catalysts (WOCs) in acidic electrolytes usually contain expensive noble metals such as ruthenium and iridium. However, they too expensive to be implemented broadly in semiconductor photoanodes for photoelectrochemical (PEC) water splitting devices. Here, an Earth-abu...
| Autores: | , , , , , , , , , , , , , , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 2019 |
| País: | España |
| Institución: | Universitat Autònoma de Barcelona |
| Repositorio: | Dipòsit Digital de Documents de la UAB |
| Idioma: | inglés |
| OAI Identifier: | oai:ddd.uab.cat:220647 |
| Acceso en línea: | https://ddd.uab.cat/record/220647 https://dx.doi.org/urn:doi:10.1002/aenm.201901836 |
| Access Level: | acceso abierto |
| Palabra clave: | Acidic electrolyte Hematite Photoelectrochemical water splitting Surface states |
| Sumario: | State-of-the-art water-oxidation catalysts (WOCs) in acidic electrolytes usually contain expensive noble metals such as ruthenium and iridium. However, they too expensive to be implemented broadly in semiconductor photoanodes for photoelectrochemical (PEC) water splitting devices. Here, an Earth-abundant CoFe Prussian blue analogue (CoFe-PBA) is incorporated with core-shell FeO/FeTiO type II heterojunction nanowires as composite photoanodes for PEC water splitting. Those deliver a high photocurrent of 1.25 mA cm at 1.23 V versus reversible reference electrode in acidic electrolytes (pH = 1). The enhancement arises from the synergic behavior between the successive decoration of the hematite surface with nanolayers of FeTiO and then, CoFe-PBA. The underlying physical mechanism of performance enhancement through formation of the FeO/FeTiO/CoFe-PBA heterostructure reveals that the surface states' electronic levels of hematite are modified such that an interfacial charge transfer becomes kinetically favorable. These findings open new pathways for the future design of cheap and efficient hematite-based photoanodes in acidic electrolytes. |
|---|