Peroxo group enhanced nanorutile as visible light active photocatalyst

• Published in: Catalysis today Vol. 284; pp. 129 - 136
• Main Authors: Gyulavári, Tamás, Pap, Zsolt, Kovács, Gábor, Baia, Lucian, Todea, Milica, Hernádi, Klára, Veréb, Gábor
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.04.2017
• Subjects: Peroxo group; Phenol; Rutile; Titanium dioxide; Visible light excitability; Phenol; Peroxo group; Rutile; Visible light excitability; Titanium dioxide
• ISSN: 0920-5861; 1873-4308
• DOI: 10.1016/j.cattod.2016.11.012

[Display omitted] •Peroxo groups can be prepared on the surface of rutile by the addition of H2O2.•Successful formation of peroxo groups needs an optimal Ti: H2O2 ratio.•Peroxo groups enhanced the visible light excitability of rutile TiO2. Hydrogen peroxide was applied during the synthesis to enhance the visible light excitability of nanosized (<10nm), pure rutile phase titanium dioxides synthesized by a facile, sol-gel method at low temperature. Different amounts of hydrogen peroxide were used during the synthesis to form peroxo groups on the surface of TiO2-s. As-prepared photocatalysts were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), infrared spectroscopy (IR), and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of the catalysts were investigated by phenol, Rhodamine B dye and coumarin degradation under visible light irradiation. Evonik Aeroxide P25 TiO2 and commercial rutile phase titanium dioxide were used as reference photocatalysts. First order derivative of DRS spectra showed enhanced visible light excitability in the case of Ti:H2O2=1:2 ratio (applied during the synthesis). XPS measurements confirmed the formation of peroxo groups in this specific TiO2. Photocatalytic measurements pointed out that this TiO2 had by far the best photocatalytic performance, exceeding the photocatalytic activity of Aeroxide P25 and commercial rutile as well. This activity gain was attributed to the presence of peroxo groups on the surface.