{"title":"Silver Modified TiO2\/Halloysite Thin Films for Decontamination of Target Pollutants","authors":"Dionisios Panagiotaras, Elias Stathatos, Dimitrios Papoulis","volume":93,"journal":"International Journal of Chemical and Molecular Engineering","pagesStart":914,"pagesEnd":921,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/9999189","abstract":"
Sol-gel method has been used to fabricate
\r\nnanocomposite films on glass substrates composed halloysite clay
\r\nmineral and nanocrystalline TiO2. The methodology for the synthesis
\r\ninvolves a simple chemistry method utilized nonionic surfactant
\r\nmolecule as pore directing agent along with the acetic acid-based solgel
\r\nroute with the absence of water molecules. The thermal treatment
\r\nof composite films at 450oC ensures elimination of organic material
\r\nand lead to the formation of TiO2 nanoparticles onto the surface of
\r\nthe halloysite nanotubes. Microscopy techniques and porosimetry
\r\nmethods used in order to delineate the structural characteristics of the
\r\nmaterials. The nanocomposite films produced have no cracks and
\r\nactive anatase crystal phase with small crystallite size were deposited
\r\non halloysite nanotubes. The photocatalytic properties for the new
\r\nmaterials were examined for the decomposition of the Basic Blue 41
\r\nazo dye in solution. These, nanotechnology based composite films
\r\nshow high efficiency for dye’s discoloration in spite of different
\r\nhalloysite quantities and small amount of halloysite\/TiO2 catalyst
\r\nimmobilized onto glass substrates. Moreover, we examined the
\r\nmodification of the halloysite\/TiO2 films with silver particles in order
\r\nto improve the photocatalytic properties of the films. Indeed, the
\r\npresence of silver nanoparticles enhances the discoloration rate of the
\r\nBasic Blue 41 compared to the efficiencies obtained for unmodified
\r\nfilms.<\/p>\r\n","references":"[1] G. A. Umbuzeiro, H.S. Freeman, S. H. Warren, D. P. Oliveira, Y. Terao,\r\nT. Watanabe and D. D. Claxton, \"The contribution of azo dyes to the\r\nmutagenic activity of the Cristais River,\u201dChemosp., vol. 60, pp. 55-64,\r\nJune 2005.\r\n[2] Y.E. Benkli, M.F. Can, M. Turan and M.S. \u00c7elik, \"Modification of\r\norgano-zeolite surface for the removal of reactive azo dyes in fixed-bed\r\nreactors,\u201d Water Res., vol.39, pp. 487-493, January\u2013February 2005.\r\n[3] E. Forgacs, T. Cserh\u00e1ti and G. Oros, \"Removal of synthetic dyes from\r\nwastewaters: a review,\u201d Environ.Int., vol. 30, pp. 953-971, September\r\n2004.\r\n[4] V. K. Gupta, J. Rajeev, N. Arunima, A. Shilpi and M. Shrivastava,\r\n\"Removal of the hazardous dye\u2014Tartrazine by photodegradation on\r\ntitanium dioxide surface,\u201dMat. Sci. Engineer.C, vol. 31, pp. 1062-1067,\r\n2011.\r\n[5] M. I. 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