Design of Multifunctional Titania-Based Photocatalysts by Controlled Redox Reactions
| Autor: | Jorge R. Frade, Enrique Rodríguez-Castellón, Diogo Lopes, Artur R. Sarabando, Blanca I. Arias-Serrano, Elena Rodríguez-Aguado, Tito Trindade, Andrei V. Kovalevsky, Ana L. Daniel-da-Silva |
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| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Anatase
Materials science redox reaction 02 engineering and technology 010402 general chemistry 01 natural sciences lcsh:Technology Article Carbide law.invention Reaction rate law silicon carbide TiO2 General Materials Science Calcination Photodegradation lcsh:Microscopy lcsh:QC120-168.85 lcsh:QH201-278.5 lcsh:T 021001 nanoscience & nanotechnology Microstructure 0104 chemical sciences Taguchi plan Chemical engineering Rutile lcsh:TA1-2040 Photocatalysis lcsh:Descriptive and experimental mechanics lcsh:Electrical engineering. Electronics. Nuclear engineering anatase 0210 nano-technology lcsh:Engineering (General). Civil engineering (General) lcsh:TK1-9971 photocatalysis |
| Zdroj: | Materials Volume 13 Issue 3 Materials, Vol 13, Iss 3, p 758 (2020) |
| ISSN: | 1996-1944 |
| DOI: | 10.3390/ma13030758 |
| Popis: | This work aims at the preparation of multifunctional titania-based photocatalysts with inherent capabilities for thermal co-activation and stabilisation of anatase polymorph, by designing the phase composition and microstructure of rutile-silicon carbide mixture. The processing involved a conventional solid state route, including partial pre-reduction of rutile by SiC in inert Ar atmosphere, followed by post-oxidation in air. The impacts of processing conditions on the phase composition and photocatalytic activity were evaluated using Taguchi planning. The XRD studies confirmed the presence of rutile/anatase mixtures in the post-oxidised samples. The results emphasise that pre-reduction and post-oxidation temperatures are critical in defining the phase composition, while post-oxidation time is relevant for the photocatalytic performance. Microstructural studies revealed the formation of core-shell particles, which can suppress the photocatalytic activity. The highest apparent reaction rate of the photodegradation of methylene blue was observed for the sample pre-reduced in Ar at 1300 ° C for 5 h and then calcined in air at 400 ° C for 25 h. Though its performance was ~1.6-times lower than that for the same amount of nanostructured industrial P25 photocatalyst, it was achieved in the material possessing 2&ndash 3 times lower surface area and containing ~50 mol% of SiO2 and SiC, thus demonstrating excellent prospects for further improvements. |
| Databáze: | OpenAIRE |
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