Papers by Keyword: Germania

Abstract: Silica nanowires have recently been grown via the vapor-liquid-solid growth mechanism where the vapor precursor is obtained directly from the substrate via active oxidation processes. In this study, we extend this technique to the Ge-O system and show that Au coated Ge substrates can be used as a volatile GeO source, resulting in germania nanowire formation above 550°C. The process is highly dependent on Au and native oxide thickness’, the partial pressure of O₂ and annealing temperature. If the oxide layer is too thick, the bare wafer is protected from the active oxidation process. However, if the oxide layer is too thin, it will be readily decomposed leaving no stable surface for nanowires to grow and only an etched surface is observed. In this study we show that a native Ge oxide is unstable and that a thicker oxide is required as a buffer layer, separating active oxidation and nanowire nucleation processes. We also show that nanowires can be grown on stable oxide particles present on the Ge wafer surface.

Abstract: The advantages and uniqueness of the Inorganic modification of the Sol-Gel method have already been described. Homogeneous nano-composites as well as some exotic glasses, complex-metal-oxides systems with little glass-forming ability, can be produced by this method. Thus, the obtained materials are characterized by a complex structure that leads to the wide variety of physical and chemical properties. Zirconia-containing materials are of utmost interest because of the mechanical toughness and chemical resistance provided by the presence of ZrO2. In the present work, we report on unusual structural peculiarities of the Zr-O, two types of Zr-Ge-O systems (with Zr>Ge and Zr

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