Abstract
TiO2 nanotube arrays grown by anodization were coated with thin layers of polydopamine as visible light sensitizer. The PDA-coated TiO2 scaffolds were used as photocatalyst for selective oxidation of benzyl alcohol under monochromatic irradiation at 473 nm. Benzaldehyde was selectively formed and no by-products could be detected. A maximized reaction yield was obtained in O2-saturated acetonitrile. A mechanism is proposed that implies firstly the charge carrier generation in polydopamine as a consequence of visible light absorption. Secondly, photo-promoted electrons are injected in TiO2 conduction band, and subsequently transferred to dissolved O2 to form O2 ·− radicals. These radicals react with benzyl alcohol and lead to its selective dehydrogenation oxidation towards benzaldehyde.
| Original language | English |
|---|---|
| Pages (from-to) | 5353-5358 |
| Number of pages | 6 |
| Journal | Journal of nanoscience and nanotechnology |
| Volume | 16 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 2016 |
| Externally published | Yes |