Super-hydrophobic fluorination mesoporous MCF/TiO2 composite as a high-performance photocatalyst

NH4F was used instead of conventional organic silylation agent as the hydrophobic modifier to synthesize the super-hydrophobic mesocellular foams (MCF) loaded with nano-sized TiO2 photocatalysts in its pore channels, which could be considered as an extractant for organics. Compared to organosilane modified catalysts, NH4F-modified MCF/TiO2 has a more stable super-hydrophobic property and much higher photocatalytic activity. It was found that only using isopropanol as the solvent, the NH4F-modified catalyst showed super-hydrophobic property. It is believed that the solvent plays a role in controlling the exchange between surface OH groups and F ions. The special structure of supported mesoporous catalyst greatly facilitated the surface fluorination, which together with the Ti3+ generation led to its excellent adsorption capacity and UV/visible light photocatalytic activity. This novel super-hydrophobic mesoporous photocatalyst has a large application potential in the field of photocatalysis, shipbuilding, and other industries.

Graphical abstractNH4F was used as hydrophobic modifier to synthesize the superhydrophobic mesocellular foams loaded with TiO2 photocatalyst, which could be considered as an extractant for organics and a high-performance photocatalyst.Figure optionsDownload full-size imageDownload high-quality image (275 K)Download as PowerPoint slideHighlights► Superhydrophobic mesoporous MCF as supports for TiO2 photocatalysts are prepared. ► NH4F is instead of unstable organic silylation agent as the hydrophobic modifier. ► Isopropanol is used as the only effective solvent to achieve the hydrophobicity. ► Low-temperature vacuum activation can produce Ti3+. ► Synergistic effect of Ti3+ and surface fluorination is responsible for its enhanced adsorption capacity and photocatalytic activity.