title: Palladium nanoparticle deposition via precipitation: a new method to functionalize macroporous silicon.
abstract: We present an original two-step method for the deposition via precipitation of Pd nanoparticles into macroporous silicon. The method consists in immersing a macroporous silicon sample in a PdCl2/DMSO solution and then in annealing the sample at a high temperature. The impact of composition and concentration of the solution and annealing time on the nanoparticle characteristics is investigated. This method is compared to electroless plating, which is a standard method for the deposition of Pd nanoparticles. Scanning electron microscopy and computerized image processing are used to evaluate size, shape, surface density and deposition homogeneity of the Pd nanoparticles on the pore walls. Energy-dispersive x-ray spectroscopy (EDX) and x-ray photoelectron spectroscopy (XPS) analyses are used to evaluate the composition of the deposited nanoparticles. In contrast to electroless plating, the proposed method leads to homogeneously distributed Pd nanoparticles along the macropores depth with a surface density that increases proportionally with the PdCl2concentration. Moreover EDX and XPS analysis showed that the nanoparticles are composed of Pd in its metallic state, while nanoparticles deposited by electroless plating are composed of both metallic Pd and PdOx.
authors.affiliation: SMALL, Institute of Information and Communication Technologies, Electronics and Applied Mathematics, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
authors.forename: Gilles
authors.initials: G
authors.lastname: Scheen
authors.affiliation: Max Planck Research Group Micro- and Nanotechnology,Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Margherita
authors.initials: M
authors.lastname: Bassu
authors.affiliation: SMALL, Institute of Information and Communication Technologies, Electronics and Applied Mathematics, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
authors.forename: Antoine
authors.initials: A
authors.lastname: Douchamps
authors.affiliation: Service de Science des Matériaux, Faculté Polytechnique, Université de Mons, Mons, Belgium.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Service de Science des Matériaux, Faculté Polytechnique, Université de Mons, Mons, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Debliquy
authors.affiliation: SMALL, Institute of Information and Communication Technologies, Electronics and Applied Mathematics, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
authors.forename: Laurent A
authors.initials: LA
authors.lastname: Francis
keywords: functionalization; macroporous silicon; palladium nanoparticles