Silver-modified titanium dioxide thin films for efficient photodegradation of methyl orange

Arabatzis, IM; Stergiopoulos, T; Bernard, MC; Labou, D; Neophytides, SG; Falaras, P

dc.contributor.author	Arabatzis, IM	en
dc.contributor.author	Stergiopoulos, T	en
dc.contributor.author	Bernard, MC	en
dc.contributor.author	Labou, D	en
dc.contributor.author	Neophytides, SG	en
dc.contributor.author	Falaras, P	en
dc.date.accessioned	2014-03-01T01:19:32Z
dc.date.available	2014-03-01T01:19:32Z
dc.date.issued	2003	en
dc.identifier.issn	0926-3373	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/15554
dc.subject	Doctor-blade technique	en
dc.subject	Methyl orange	en
dc.subject	Photocatalyst activity	en
dc.subject	Pollutant degradation	en
dc.subject	Silver deposition	en
dc.subject	TiO2 nanocrystalline thin films	en
dc.subject.classification	Chemistry, Physical	en
dc.subject.classification	Engineering, Environmental	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	Catalyst activity	en
dc.subject.other	Photocatalysis	en
dc.subject.other	Photodegradation	en
dc.subject.other	Rate constants	en
dc.subject.other	Silver	en
dc.subject.other	Thin films	en
dc.subject.other	Ultraviolet radiation	en
dc.subject.other	Titanium dioxide thin films	en
dc.subject.other	Titanium dioxide	en
dc.title	Silver-modified titanium dioxide thin films for efficient photodegradation of methyl orange	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/S0926-3373(02)00233-3	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S0926-3373(02)00233-3	en
heal.language	English	en
heal.publicationDate	2003	en
heal.abstract	Silver-modified, rough, high surface area titanium dioxide thin films resulting via a two-step dipping and UV-irradiation process were examined for their catalytic activity towards photodegradation of methyl orange (MO). Optimization of the photocatalyst's performance as a function of the dipping time, irradiation time and the dipping solution concentration was performed. The optimum silver nitrate concentration of the dipping solution was found to be 10(-3) M. The modified materials present enhanced photocatalytic efficiency and can decompose the organic pollutant three-times faster than the undoped original films (Degussa P25). A further Ag+-ion concentration increase in dipping solution results a decrease of the films photocatalyst efficiency due to a shading of the available semiconductor surface by the silver layer. This performance is consistent with the unique structural, morphological, and surface characteristics of the composite silver/titania materials. The lower the average particle size, roughness and fractal dimension, the higher the photodegradation percentage and rate constants. The surface doping effect is synergetic to the charge separation process and the photocatalytic results are explained on the basis of a mechanism involving efficient separation of electron-hole pairs induced by silver-ions (Ag+). Reproducibility tests proved that the photocatalytic activity of the silver-modified films remains intact even after six consecutive experiments of new added pollutant quantities. (C) 2002 Elsevier Science B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Applied Catalysis B: Environmental	en
dc.identifier.doi	10.1016/S0926-3373(02)00233-3	en
dc.identifier.isi	ISI:000182553700006	en
dc.identifier.volume	42	en
dc.identifier.issue	2	en
dc.identifier.spage	187	en
dc.identifier.epage	201	en