Tailoring of highly porous SnO2 and SnO2-Pd thin films

Abstract Tin oxide is a material that attracts attention due to variety of technological applications. The main parameters that influence its properties are morphology, crystalline structure and stoichiometry. Researchers try to develop nanostructured thin films with tunable parameters that would conform its technological applications. Herein, we report on the preparation and characterization of highly porous SnO2 and Pd-doped SnO2 thin films. These films were deposited in the form of nanorods with controllable geometry. Such morphology was achieved by utilizing glancing angle deposition (GLAD) with assisted magnetron sputtering. This arrangement allowed preparation of slanted pillars, zig-…

In-situ electrochemical atomic force microscopy study of aging of magnetron sputtered Pt-Co nanoalloy thin films during accelerated degradation test

Abstract A Pt-Co nanoalloy thin film catalyst was prepared by using simultaneous magnetron sputtering of Pt and Co. The catalyst was characterized during accelerated degradation test using in-situ electrochemical atomic force microscopy complemented with ex-situ techniques such as energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and synchrotron radiation photoelectron spectroscopy. The combined results gave the full step-by-step picture of the catalyst behavior during the aging test.

Maximum Noble-Metal Efficiency in Catalytic Materials: Atomically Dispersed Surface Platinum

International audience; Platinum is the most versatile element in catalysis, but it is rare and its high price limits large-scale applications, for example in fuel-cell technology. Still, conventional catalysts use only a small fraction of the Pt content, that is, those atoms located at the catalyst's surface. To maximize the noble-metal efficiency, the precious metal should be atomically dispersed and exclusively located within the outermost surface layer of the material. Such atomically dispersed Pt surface species can indeed be prepared with exceptionally high stability. Using DFT calculations we identify a specific structural element, a ceria ``nanopocket'', which binds Pt2+ so strongly…

Back Cover: Maximum Noble-Metal Efficiency in Catalytic Materials: Atomically Dispersed Surface Platinum (Angew. Chem. Int. Ed. 39/2014)

Rücktitelbild: Auf dem Weg zu größtmöglicher Effizienz bei der katalytischen Nutzung von Edelmetallen: atomar dispergiertes Oberflächen-Platin (Angew. Chem. 39/2014)

Auf dem Weg zu größtmöglicher Effizienz bei der katalytischen Nutzung von Edelmetallen: atomar dispergiertes Oberflächen-Platin

Platin ist das am vielseitigsten eingesetzte Element in der Katalyse. Allerdings begrenzt der hohe Preis des Edelmetalls die Verwendung in vielen Bereichen, z. B. in Katalysatormaterialien fur Brennstoffzellen. Trotzdem nutzen konventionelle Katalysatoren oftmals nur einen Bruchteil ihres Pt-Gehaltes, namlich diejenigen Atome, die sich auf der Oberflache des Katalysators befinden. Eine effizientere Edelmetallnutzung setzt somit eine hohere, bevorzugt atomare Dispersion der Pt-Atome auf der Oberflache voraus. Tatsachlich ist es moglich, solche atomar dispergierten Pt-Spezies mit sehr hoher Stabilitat auf einer Katalysatoroberflache herzustellen. Mithilfe von DFT-Rechnungen identifizieren wir…