title: Photocatalytic synthesis of silver nanoparticles stabilized by TiO2 nanorods: a semiconductor/metal nanocomposite in homogeneous nonpolar solution.
abstract: A novel colloidal approach toward semiconductor/metal nanocomposites is presented. Organic-soluble anatase TiO(2) nanorods are used for the first time to stabilize Ag nanoparticles in optically clear nonpolar solutions in the absence of specific ligands for silver. Metallic silver is generated upon UV illumination of deaerated TiO(2) solutions containing AgNO(3). The Ag nanoparticles can be obtained in different size-morphological regimes as a function of the irradiation time, due to light-induced photofragmentation and ripening processes. A mechanism for the colloidal stabilization of the silver nanoparticles is tentatively suggested, which regards the TiO(2) nanorods as inorganic stabilizers, thus acting in the same manner as conventional surfactant molecules. The proposed photocatalytic approach offers a convenient method for producing TiO(2)/Ag nanocomposite systems with a certain control over the metal particle size without the use of surfactants and/or additives. Stable colloidal TiO(2)-nanorod-stabilized Ag nanoparticles can be potentially available for a number of applications that require "clean" metal surfaces, such as homogeneous organic catalysis, photocatalysis, and sensing devices.
authors.affiliation: Dipartimento di Chimica, Università di Bari, Via Orabona 4, 70126 Bari, Italy.
authors.forename: P Davide
authors.initials: PD
authors.lastname: Cozzoli
authors.forename: Roberto
authors.initials: R
authors.lastname: Comparelli
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Fanizza
authors.forename: M Lucia
authors.initials: ML
authors.lastname: Curri
authors.forename: Angela
authors.initials: A
authors.lastname: Agostiano
authors.forename: Danièle
authors.initials: D
authors.lastname: Laub