Photoinduced Electron Transfer from Nitrogen-Doped Tantalum Oxide to Adsorbed Ruthenium Complex
| Autor: | Shunsuke Sato, Tsutomu Kajino, Takeshi Morikawa, Masayo Iwaki, Ken-ichi Yamanaka |
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| Rok vydání: | 2011 |
| Předmět: |
Reaction mechanism
Chemistry Infrared Quantum yield chemistry.chemical_element Photochemistry Photoinduced electron transfer Surfaces Coatings and Films Electronic Optical and Magnetic Materials Ruthenium Electron transfer General Energy Reaction rate constant Physical and Theoretical Chemistry Absorption (chemistry) |
| Zdroj: | The Journal of Physical Chemistry C. 115:18348-18353 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/jp205223k |
| Popis: | To understand the photoinduced electron-transfer process and the reaction mechanism of semiconductor/metal-complex hybrid CO2-reducing photocatalysts, the excited-state dynamics of nitrogen-doped Ta2O5 (N–Ta2O5) and that adsorbed with Ru complexes (Ru/N–Ta2O5) were investigated. Upon adsorption of the Ru complex ([Ru(dcbpy)2(CO)2]2+) on N–Ta2O5 powder, one of the CO ligands was exchanged to COOH ([Ru(dcbpy)2(CO)(COOH)]+), which resulted in absorption spectral changes in UV/visible and infrared regions (dcbpy: 4,4′-dicarboxy-2,2′-bipyridine). A detailed analysis of time-resolved emission measurements after excitation at 400 nm (Ta 4f ← N 2p transition) revealed a fast trapping process from shallow defect sites to deep defect sites with a time constant of 24 ± 1 ps in N–Ta2O5 powder. In Ru/N–Ta2O5, ultrafast electron transfer from the shallow defect sites of N–Ta2O5 to the adsorbed Ru complex occurred with a time constant of 12 ± 1 ps. The values of rate constant (ket) and quantum yield (Φet) of the electro... |
| Databáze: | OpenAIRE |
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