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Abstract: Ultrafast formation of high-aspect ratio titanium dioxide nanotube is carried out by the rapid-breakdown-anodizing technique using a two compartment electrochemical cell. The change in surface morphology of the titanium substrate during anodization, and physical parameters such as pH and temperature are investigated. Under optimized conditions, aligned TiO2 nanotube powder is obtained that beneficially can be used in dye-sensitized solar cells. Solar cell constructed using the nanotube powder can show a significantly higher open circuit voltage than when constructed with commercially available nanoparticles. [Copyright &y& Elsevier]

Abstract: A simple method for the formation of palladium nanoparticles on aluminum and aluminum oxide surface is demonstrated. In the present method, the palladium nanoparticles obtained directly on the solid surface by immersing the specimen in palladium(II)acetate solution followed by reduction to metallic palladium by using sodium hypophosphite. In the investigation, as-received, boiled, electropolished and anodized aluminum was used as substrate. Additionally, the method is combined with the electroless nickel plating, which facilitates two steps metallization technique on the respective surfaces. In these cases, specimens were first immersed in palladium(II)acetate solution followed by immersion in electroless nickel plating solution, where, palladium reduced on the specimen surface providing catalytic site for the subsequent electroless nickel deposition. Using the technique, about 6 to 8.5 µm thick Ni–P metallic layer was deposited on the specimen surface. [Copyright &y& Elsevier]

Abstract: In the present work we demonstrate the fabrication and use of a new generation of TiO2 nanotube membranes. We show that anodic oxide nanotube growth can be performed through a patterned Ti foil into an underlying Al metal layer. After the selective dissolution of the Al/alumina layer, a very well defined both side open suspended TiO2 nanotube layer can be obtained. Using lithographic patterning of the anodization area allows to achieve very large scale, flexible and well electrically connected nanotubular flow-through membranes with fast electrical switching features over the entire membrane. [ABSTRACT FROM AUTHOR]

Photocatalytic approaches, that is the reaction of light-produced charge carriers at a semiconductor surface with their environment, currently attract an extremely wide scientific interest. This is to a large extent due to the high expectations: i) to convert sunlight directly into an energy carrier (H(2)), ii) to stimulate chemical synthetic reactions, or iii) to degrade unwanted environmental pollutants. Since the early reports in 1972, TiO(2) has been the most investigated photocatalytic material by far; this originates from its outstanding electronic properties that allow for a wide range of applications. Not only the material, but also its structure and morphology, can have a considerable influence on the photocatalytic performance of TiO(2). In recent years, particularly 1D (or pseudo 1D) structures such as nanowires and nanotubes have received great attention. The present Review focuses on TiO(2) nanotube arrays (and similar structures) that grow by self-organizing electrochemistry (highly aligned) from a Ti metal substrate. Herein, the growth, properties, and applications of these tubes are discussed, as well as ways and means to modify critical tube properties. Common strategies are addressed to improve the performance of photocatalysts such as doping or band-gap engineering, co-catalyst decoration, junction formation, or applying external bias. Finally, some unique applications of the ordered tube structures in various photocatalytic approaches are outlined., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nb-doped TiO(2) nanotube (with C(Nb) < 1 wt%) layers were successfully fabricated by self-ordered electrochemical anodization of Ti-Nb alloys. When used in dye-sensitized solar cells the efficiency enhanced by up to 30% compared to non-doped TiO(2) nanotubes. IMVS measurements indicate the beneficial effect to be due to lower recombination losses.