TiO2-polyheptazine hybrid photoanodes: Effect of cocatalysts and external bias on visible light-driven water splitting
| Autor: | Lidong Wang, Radim Beranek, Michal Bledowski, Ayyappan Ramakrishnan |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Materials science
Mechanical Engineering Inorganic chemistry Oxygen evolution Oxide chemistry.chemical_element Condensed Matter Physics Photochemistry chemistry.chemical_compound chemistry Mechanics of Materials Electrode Water splitting General Materials Science Irradiation Iridium Deposition (law) Visible spectrum |
| Zdroj: | Journal of Materials Research. 28:411-417 |
| ISSN: | 2044-5326 0884-2914 |
| DOI: | 10.1557/jmr.2012.297 |
| Popis: | Photoanodes based on TiO2-polyheptazine (TiO2-PH) hybrids are, due to the energetics of photogenerated charges, very promising for solar water splitting in terms of possibly reduced need for external electric bias. Visible (λ > 420 nm) light-driven photooxidation of water at TiO2-PH electrodes loaded with two different metal oxide cocatalysts was investigated. As compared with TiO2-PH photoanodes loaded with colloidal [iridium (IV) oxide] IrO2 deposited by colloidal deposition, photoelectrodes modified with CoOx oxygen-evolving cocatalyst (Co-Pi) deposited by photoassisted deposition precipitation method showed both higher photocurrents and more efficient oxygen evolution under prolonged irradiation. The minimum external electric bias needed to observe complete photooxidation of water to dioxygen at TiO2-PH photoanodes modified with Co-Pi was estimated to be ∼0.6 V at pH 7. The key factor limiting the photoconversion efficiency at low bias potentials is the fast primary recombination of photogenerated charges. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full text from SpringerLink