Size-Selective Synthesis and Stabilization of Small Silver Nanoparticles on TiO2 Partially Masked by SiO2
| Autor: | Christian P. Canlas, Justin M. Notestein, Jeffrey T. Miller, James R. Gallagher, Zhenyu Bo, Todd R. Eaton |
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| Rok vydání: | 2015 |
| Předmět: |
Materials science
General Chemical Engineering Dispersity Oxide Nanoparticle Sintering Nanotechnology General Chemistry Silver nanoparticle Catalysis Metal chemistry.chemical_compound chemistry Chemical engineering Transmission electron microscopy visual_art Materials Chemistry visual_art.visual_art_medium |
| Zdroj: | Chemistry of Materials. 27:1269-1277 |
| ISSN: | 1520-5002 0897-4756 |
| Popis: | Controlling metal nanoparticle size is one of the principle challenges in developing new supported catalysts. Typical methods where a metal salt is deposited and reduced can result in a polydisperse mixture of metal nanoparticles, especially at higher loading. Polydispersity can exacerbate the already significant challenge of controlling sintering at high temperatures, which decreases catalytic surface area. Here, we demonstrate the size-selective photoreduction of Ag nanoparticles on TiO2 whose surface has been partially masked with a thin SiO2 layer. To synthesize this layered oxide material, TiO2 particles are grafted with tert-butylcalix[4]arene molecular templates (∼2 nm in diameter) at surface densities of 0.05–0.17 templates.nm–2, overcoated with ∼2 nm of SiO2 through repeated condensation cycles of limiting amounts of tetraethoxysilane (TEOS), and the templates are removed oxidatively. Ag photodeposition results in uniform nanoparticle diameters ≤ 3.5 nm (by transmission electron microscopy (TEM))... |
| Databáze: | OpenAIRE |
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