Pt-TiO₂ Nanocomposites in Alginate for Enhancing Photocatalytic Activity

Abstract:

A new sol-gel method was employed to synthesize Pt-containing titania composite with varied dopant concentrations using alginate as an template for preventing inorganic materials conglomeration. During the calcination process, the Pt nanoparticles, which had been loaded in alginate porous networks, were doped into the titania system. The morphology and crystallization behavior of titania were characterized. HAAD-STEM image and EDX spectroscopy of Pt/TiO₂ composites confirmed that Pt was well embodied into the TiO₂ mesoporous network. The UV-vis diffuse reflection spectra at room temperature shown that the Pt/TiO₂ composite exhibited a marked visible light adsorption compared with a pure TiO₂ sample. The photocatalytic activities were tested using phenol as the model compound, and the results demonstrated that higher photocatalytic activity was observed at higher levels of Pt added to the titania system. The optimum dopant concentration was found to be 0.37 mol % for Pt/TiO₂ sample.

• Periodical: Advanced Materials Research (Volume 936)
• Pages: 300-303
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.936.300
• Online since: June 2014
• Authors: Yun Run Wang*
• Keywords: Alginate, Nanocomposite, Phenol, Photocatalytic Activity, Pt/TiO₂

References

[1] M. Sidheswaran, L. L. Tavlarides, Characterization and Visible Light Photocatalytic Activity of Cerium- and Iron-Doped Titanium Dioxide Sol−Gel Materials. Ind. Eng. Chem. Res. 48 (2009) 10292-10306.

DOI: 10.1021/ie900773m

[2] M. R. Hoffmann, S. T. Martin, W. Choi, D. W. Bahnemann, Environmental Applications of Semiconductor Photocatalysis, Chem. Rev. 95 (1995) 69-96.

DOI: 10.1021/cr00033a004

[3] M. Mrowetz, W. Balcerski, A. J. Colussi, M. R. Hoffmann, Oxidative Power of Nitrogen-Doped TiO2 Photocatalysts under Visible Illumination, J. Phys. Chem. B. 108(2004)17269-17273.

DOI: 10.1021/jp0467090

[4] A. Di Paola, G. Marci, L. Palmisano, M. Schiavello, K. Uosaki, S. Ikeda, B. Ohtani, Preparation of Polycrystalline TiO2 Photocatalysts Impregnated with Various Transition Metal Ions:  Characterization and Photocatalytic Activity for the Degradation of 4-Nitrophenol, J. Phys. Chem. B. 106 (2002).

DOI: 10.1021/jp013074l

[5] V. Subramanian, E. E. Wolf, P. V. Kamat, Catalysis with TiO2/Gold Nanocomposites. Effect of Metal Particle Size on the Fermi Level Equilibration, J. Am. Chem. Soc. 126 (2004), 4943-4950.

DOI: 10.1021/ja0315199

[6] P. Chen, X. Zhang, Z. Miao, B. Han, G. An, Z. Liu, In-site synthesis of noble metal nanoparticles in alginate solution and their application in catalysis. J. Nanosci. Nanotechnol. 9 (2009) 2628-2632.

[7] P. Chen, X. Zhang, Fabrication of Pt/TiO2 Nanocomposite in alginate and their applications to the degradation of phenol and methylene blue in aqueous solution, Clean. 36 (2008) 507-511.

DOI: 10.1002/clen.200800089