title: Palladium Electrodeposition onto Pt(100): Two-Layer Underpotential Deposition.
abstract: Electrodeposition of the first Pd layers onto Pt(100) was investigated using cyclic voltammetry at a low scan rate (0.1 mV·s-1). Ultrathin films were characterized by cyclic voltammetry in 0.1 M H2SO4solution and with ex situ AFM (atomic force microscopy). For the first time, we evidenced the underpotential character of the deposition of the first two Pd layers, characterized by a two-step mechanism, each step corresponding to the deposition of a complete Pd atomic layer. For thicker deposits, especially above 10 monolayers as equivalent thickness, the electrochemical characterization displays a strong irreversibility and a broadening of the adsorption/desorption peaks, associated with a reduction of long-range ordered flat areas. Ex situ AFM images are in agreement with this description. They show rough thick deposits and the growth of (100)-oriented rectangular shaped islands with their sides aligned with the two [011] and [0-11] perpendicular directions of the (100) Pt surface.
authors.affiliation: University Grenoble Alpes, LEPMI , F-38000 Grenoble, France.|CNRS, LEPMI, F-38000 Grenoble, France.
authors.forename: Bruno A F
authors.initials: BA
authors.lastname: Previdello
authors.affiliation: University Grenoble Alpes, LEPMI , F-38000 Grenoble, France.|CNRS, LEPMI, F-38000 Grenoble, France.
authors.forename: Eric
authors.identifier: 0000-0003-4084-1624
authors.initials: E
authors.lastname: Sibert
authors.affiliation: University Grenoble Alpes , SiMAP, F-38000 Grenoble, France.|CNRS, SiMAP, F-38000 Grenoble, France.
authors.forename: Mireille
authors.initials: M
authors.lastname: Maret
authors.affiliation: University Grenoble Alpes, LEPMI , F-38000 Grenoble, France.|CNRS, LEPMI, F-38000 Grenoble, France.|CNRS, Institut Néel, F-38042 Grenoble, France.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Soldo-Olivier