Electron injection from a carboxylic anchoring dye to TiO2 nanoparticles in aprotic solvents
| Autor: | Yi Rao, Hai-Lung Dai, Zachary Zander, Danielle L. Kuhn, Brendan G. DeLacy, Hui Fang, Yuhao Wu |
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| Rok vydání: | 2018 |
| Předmět: |
Anatase
Chloroform General Physics and Astronomy 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Photochemistry 01 natural sciences Molecular electronic transition 0104 chemical sciences Marcus theory chemistry.chemical_compound Dye-sensitized solar cell chemistry Ultrafast laser spectroscopy Physical and Theoretical Chemistry 0210 nano-technology Acetonitrile Dichloromethane |
| Zdroj: | Chemical Physics. 512:93-97 |
| ISSN: | 0301-0104 |
| DOI: | 10.1016/j.chemphys.2018.02.022 |
| Popis: | Injection of photoexcited electrons in the para-Ethyl Red dye to TiO2 nanoparticles (Anatase, 40 nm diameter) is characterized by transient absorption on ultrafast time scales. This study focuses on understanding the effect of aprotic solvents on the injection rate. Transient absorption at 1900 cm−1 is probed following a 400 nm pulse which excites the electronic transition of p-ER adsorbed on TiO2 through its carboxylic group. Measurements conducted in three different solvents show that electron injection lifetimes are in the 250–300 fs range but display a trend in correlation with solvent polarity: the electron injection lifetime is the shortest (257 fs) in acetonitrile followed by dichloromethane (271 fs) and chloroform (296 fs). This trend can be understood by using the Marcus theory in which the reorganization energy varies correspondingly in the three different solvents. This study shows that for aprotic solvents the one with the highest polarity facilitates the fastest electron injection. |
| Databáze: | OpenAIRE |
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