Metal oxide-based nanostructures

Over last 3 years there were interesting new developments in the area of chiral metal oxide based nanostructures. 

The synthesis of nanostructured carbon using aliphatic alcohols as selfassembling molecules has demonstrated that this strategy can be extended beyond metal oxide-based materials [38]. Recently, we have reported the synthesis of a novel carbon material with tunable porosity by using a liquid-crystalline precursor containing a surfactant and a carbon-yielding chemical, furfuryl alcohol. The carbonization of the cured self-assembled carbon precursor produces a new carbon material with both controlled porosity and electrical conductivity. The unique combination of both features is advantageous for many relevant applications. For example, when tested as a supercapacitor electrode, specific capacitances over 120 F/g were obtained without the need to use binders, additives, or activation to increase surface area [38]. The proposed synthesis method is versatile and economically attractive, and allows for the precise control of the structure. 

Soler-Illia, G.J.A.A. Sanchez, C. Lebeau, B. Patarin, J. Chemical strategies to design textured silica and metal oxide-based organised networks from nanostructured networks to hierarchical structures. Chem. Rev. 2002, 102, 4093. 

Another area which was initiated during last year is development of chiral metal oxide based nanomaterials such as chiral Ti02 nanofibres and chiral ZrOj nanotubes. It is anticipated that these chiral metal oxide nanostructures will find very important applications as asymmetric catalysts. In addition the progress in the fabrication of mesoporous silica based chiral nanostructures e.g. helical architectures) should open new opportunities in chiral separation of enantiomeric compounds. 

Ansari AA, Alhoshan M, Alsalhi M, Aldwayyan A (2010) Nanostructured metal oxides based enzymatic electrochemical biosensors... 

The limited sensitivity and high operating temperature are major drawbacks for the available metal oxide-based commercial sensors. The issue of sensitivity can be overcome by using one-dimensional nanostructures because of their comparable diameters with respect to the width of the SCR. 

In conclusion, these data do not allow concluding whether or not Titania nanotubes form better catalysts due to their intrinsic nanostructure, and not simply because they have a high geometrical surface area and provide a good dispersion of supported catalysts. These properties may be found in other Titania based catalysts not having a ID nanostructure. On the other hand, it is also clear from above comments that most of the studies up to now were justified essentially from the curiosity to use a novel support more than from the rational design of advanced catalysts, which use the metal oxide nanostructure as a key component to develop... 

An efficient, low temperature oxidation catalyst was developed based on highly disperse metal catalyst on nanostructured Ti02 support. Addition of dopants inhibits metal sintering and prevents catalyst deactivation. The nanostructured catalyst was formulated to tolerate common poisons found in environments such as halogen- and sulfur-containing compounds. The nanocatalyst is capable of oxidizing carbon monoxide and common VOCs to carbon dioxide and water at near ambient temperatures (25-50 °C). 

Considering the advantageous support properties of nanocarbons discussed in Section 15.2, numerous studies have been carried out on different catalytic reactions. To highlight the positive impact of the nanostructure, this section focuses on reports that give a reference catalyst based on a conventional carbonaceous support such as activated carbon, carbon black, or graphite, rather than metal oxides. 

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