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Updated: Jun 19, 2026
11:47
The Effect of Interfacial Chemical Bonding in TiO2-SiO2 Composites on Their Photocatalytic NOx Abatement Performance
Published on: July 4, 2017
Photocatalytic activity of TiO2/SiO2 systems
M Bellardita1, M Addamo, A Di Paola
1Schiavello-Grillone Photocatalysis Group, Dipartimento di Ingegneria Chimica dei Processi e dei Materiali, Università di Palermo, Viale delle Scienze, 90128 Palermo, Italy.
Journal of Hazardous Materials
|October 16, 2009
Summary
Researchers developed silica-supported titanium dioxide (TiO2) powders for photocatalytic cements. The TiO2/Cabot sample showed excellent photoactivity, making it suitable for environmental applications like NOx abatement.
Area of Science:
- Materials Science
- Chemical Engineering
- Environmental Science
Background:
- Photocatalytic materials are crucial for environmental remediation.
- Titanium dioxide (TiO2) is a well-established photocatalyst.
- Developing efficient TiO2-based additives for construction materials like cement is an active research area.
Purpose of the Study:
- To synthesize silica-supported TiO2 powders as additives for photocatalytic cements.
- To evaluate the photocatalytic activity of TiO2 supported on different silica types.
- To identify the most effective TiO2/SiO2 composite for environmental applications.
Main Methods:
- Wet synthesis method under mild conditions.
- Preparation of TiO2/SiO2 composites using commercial silicas (Cabot, Axim, Fly Ash).
- Photocatalytic activity evaluation using 2-propanol in gas-solid batch and continuous reactors.
- Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) analysis.
Main Results:
- Titanium dioxide was quantitatively deposited on all silica supports.
- TiO2/Axim and TiO2/Fly Ash composites exhibited low photocatalytic activity.
- TiO2/Cabot composite demonstrated significant photoactivity in both batch and continuous systems.
- The TiO2/Cabot sample was further tested for NOx abatement and 4-nitrophenol photodegradation.
Conclusions:
- The purity of the silica support significantly impacts the photocatalytic performance of TiO2/SiO2 composites.
- Ultra-pure Cabot silica resulted in a highly photoactive TiO2/Cabot composite.
- The TiO2/Cabot composite shows promise as an additive for photocatalytic cements and for environmental remediation applications.
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