Photocatalytic activity of TiO2/SWCNT and TiO2/MWCNT nanocomposites with different carbon nanotube content

• Published in: Physica Status Solidi (b) Vol. 248; no. 11; pp. 2496 - 2499
• Main Authors: Vajda, Krisztina, Mogyorosi, Karoly, Nemeth, Zoltan, Hernadi, Klara, Forro, Laszlo, Magrez, Arnaud, Dombi, Andras
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01-11-2011; WILEY‐VCH Verlag; Wiley-VCH
• Subjects: Carbon nanotubes; Catalysis; Catalytic reactions; Chemistry; Concentration (composition); Degradation; Exact sciences and technology; functionalization; General and physical chemistry; MWCNT; Nanocomposites; Phenol; Photocatalysis; Scanning electron microscopy; SWCNT; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; TiO2; Titanium dioxide; Sonication; Volume fraction; Photocatalysis; Carbon nanotubes; Electron transfer; Singlewalled nanotube; Phenol; Transmission electron microscopy; Ultraviolet irradiation; Reaction mechanism; Nanocomposite; Oxidation; Aqueous solution; Scanning transmission electron microscopy; Titanium oxide; Catalyst
• ISSN: 0370-1972; 1521-3951; 1521-3951
• DOI: 10.1002/pssb.201100117

With different mass ratios, titanium dioxide/carbon nanotube (0.1–10 wt% CNT content) nanocomposites were prepared with the aid of ultrasonication method. The structures of the various TiO2/CNT nanocomposites were characterized by electron microscopy (scanning electron microscopy, transmission electron microscopy). Their photocatalytic activity was tested by the degradation of phenol in aqueous solution under near‐UV irradiation. In parallel experiments, both (SW and MW) CNT samples were treated in a reflux system with nitric acid to functionalize the nanotubes, subsequently preparing the nanocomposites in the same method. At higher CNT concentration (5, 10 wt%) the nanocomposites exhibited lower photocatalytic activity compared to the samples with lower CNT concentration, probably because the higher CNT concentration reduces the light intensity on the surfaces of TiO2 particles. Our aim was to find the best synthesis method and the optimal composition of the TiO2/CNT nanocomposites for the degradation of phenol under UV irradiation. The highest degradation rate was achieved with Aldrich anatase/functionalized single wall carbon nanotube nanocomposite (AA + f‐SW1 wt%). The photocatalytic activity of this sample was significantly higher compared to the bare Aldrich anatase and Aeroxide P25 titanium dioxide reference samples which were the best photocatalysts among the investigated bare titanias.