title: Anodic oxide formation on aluminium-terbium alloys.
abstract: Aluminium terbium alloys were prepared by simultaneous thermal evaporation resulting in a thin film library covering a 5 to 25 at.% Tb compositional spread. Synchrotron x-ray diffraction (XRD) proves all of the alloys to be amorphous. Scanning electron microscopy (SEM) measurements reveal the structural changes upon increase in Tb content with the formation of small, Tb-rich segregations right before a drastic change in morphology around 25 at.% Tb. Anodic oxides were formed systematically in cyclic voltammograms using scanning droplet cell microscopy. Coulometric analysis revealed a linear thickness over formation potential behaviour with film formation factors ranging from 1.2 nm V-1(5 at.% Tb) to 1.6 nm V-1(25 % Tb). Electrochemical impedance spectroscopy was performed for each incremental oxidation step resulting in a linear relation between inverse capacity and formation potential with dielectric constants ranging from 8 (5 at.% Tb) to 16 (25 at.% Tb).
authors.affiliation: Christian Doppler Laboratory for Combinatorial Oxide Chemistry (COMBOX) at the Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria ; Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
authors.forename: Andrei Ionut
authors.initials: AI
authors.lastname: Mardare
authors.affiliation: Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
authors.forename: Carina Daniela
authors.initials: CD
authors.lastname: Grill
authors.affiliation: Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
authors.forename: Isabella
authors.initials: I
authors.lastname: Pötzelberger
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
authors.forename: Tanja
authors.initials: T
authors.lastname: Etzelstorfer
authors.affiliation: Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
authors.forename: Julian
authors.initials: J
authors.lastname: Stangl
authors.affiliation: Christian Doppler Laboratory for Combinatorial Oxide Chemistry (COMBOX) at the Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria ; Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Str. 69, 4040 Linz, Austria.
authors.forename: Achim Walter
authors.initials: AW
authors.lastname: Hassel
keywords: Anodic oxide film; Combinatorial libraries; High-throughput experimentation; Scanning droplet cell; Terbium