Print Email Facebook Twitter Suppressing the Photocatalytic Activity of TiO2 Nanoparticles by Extremely Thin Al2O3 Films Grown by Gas-Phase Deposition at Ambient Conditions Title Suppressing the Photocatalytic Activity of TiO2 Nanoparticles by Extremely Thin Al2O3 Films Grown by Gas-Phase Deposition at Ambient Conditions Author Guo, J. (TU Delft ChemE/Product and Process Engineering; Sichuan University; North University of China) Bui, H.V. (TU Delft ChemE/Product and Process Engineering; Quy Nhon University) Valdesueiro Gonzalez, D. (TU Delft ChemE/Product and Process Engineering; Delft IMP B.V.) Yuan, Shaojun (Sichuan University) Liang, Bin (Sichuan University) van Ommen, J.R. (TU Delft ChemE/Product and Process Engineering) Date 2018 Abstract This work investigated the suppression of photocatalytic activity of titanium dioxide (TiO2) pigment powders by extremely thin aluminum oxide (Al2O3) films deposited via an atomic-layer-deposition-type process using trimethylaluminum (TMA) and H2O as precursors. The deposition was performed on multiple grams of TiO2 powder at room temperature and atmospheric pressure in a fluidized bed reactor, resulting in the growth of uniform and conformal Al2O3 films with thickness control at sub-nanometer level. The as-deposited Al2O3 films exhibited excellent photocatalytic suppression ability. Accordingly, an Al2O3 layer with a thickness of 1 nm could efficiently suppress the photocatalytic activities of rutile, anatase, and P25 TiO2 nanoparticles without affecting their bulk optical properties. In addition, the influence of high-temperature annealing on the properties of the Al2O3 layers was investigated, revealing the possibility of achieving porous Al2O3 layers. Our approach demonstrated a fast, efficient, and simple route to coating Al2O3 films on TiO2 pigment powders at the multigram scale, and showed great potential for large-scale production development Subject ultrathin Al2O3 filmsatomic layer depositionfluidized bed reactorphotocatalytic suppressionTiO2 pigments To reference this document use: http://resolver.tudelft.nl/uuid:092ee914-625b-4897-85f5-52cdae7ea7e2 DOI https://doi.org/10.3390/nano8020061 ISSN 2079-4991 Source Nanomaterials, 8 (2) Part of collection Institutional Repository Document type journal article Rights © 2018 J. Guo, H.V. Bui, D. Valdesueiro Gonzalez, Shaojun Yuan, Bin Liang, J.R. van Ommen Files PDF nanomaterials_08_00061.pdf 1.69 MB Close viewer /islandora/object/uuid:092ee914-625b-4897-85f5-52cdae7ea7e2/datastream/OBJ/view