Nanostructured preparation

Ultrasound frequency has revealed as the most important operational variable. Low frequency (20-60 kHz) has been most used to obtain mechanical effects such mass transport enhancement, shock waves, microjetting and surface vibration, especially used in the nanostructure preparation. It has been reported [118] that... 

Brust, M. and Kiely, C.J. (2002) Some recent advances in nanostructure preparation from gold and silver particles a short topical review. Colloids and Surfaces A Physicochemical and EngineeringAspects, 202 (2-3), 175-186. 

Bharathi, S., Nataraj, D., Mangalaraj, D., Masuda, Y., Senthil, K. and Yong, K. (2010) Highly mesoporous 0t-Fe2O3 nanostructures preparation, characterization and improved photocatalytic performance towards Rhodamine B (Rh B). journal of Physics D Applied Physics, 43, 015501. 

The electronic absorption spectrum of the CuS nanotubes given in Fig. 5a shows the characteristic broad band of CuS in the near IR region, peaking at 1200 nm. The band is attributed to an electron-acceptor state lying within the band gap [17]. A similar broad band has been reported for CuS nanocrystals [27], The photoluminescence spectrum of CuS nanostructures given in Fig. 5b shows a broad band peaking at 560 nm with a shoulder at 480 nm. Bulk CuS is reported to show a broad band centered at 560 nm with a shoulder at 587 nm [17], The absence of any appreciable blue-shift of the emission bands of the CuS nanostructures prepared by us might be due to the formation of chains of nanorods by self-assembly. 

Figure 11.41 TEM images of dendritic gold nanostructures produced at various ammonium formate concentrations a) 0.06, b) 0.1, c) 0.3, and d) 0.5 M. The insets are higher magnification TEM images of individual gold nanostructures prepared under the corresponding reaction conditions. Reprinted with permission from reference [100]. (2008) American Chemical Society.

In order to make a conclusion about the reasons of the absorption band enhancing we also studied the surface relief for nanostructures prepared. Figs. 2a and 2b demonstrate the surface images of the copper monolayer and the two-layer Cu-Ag structure. In both cases metal coatings are nanostructured. It is worthwhile to note that at comparable lateral mean sizes of nanoparticles (10-15 nm), nanoparticle vertical sizes in Fig. 2a are different. 

Some recent advances in nanostructure preparation from gold and silver particles a short topical review ... 

Figure 7.17 SEM images of nanocomposites with hierarchial nanostructures prepared by electrospinning followed by calcination (a) V20s-Ta205 nanorods on Ti02 nanofibers, and (b) V2O5 nanorods on Si02 nanofibers. (Reprinted with permission from R. Ostermann et al. Nano Lett. 2006, 6, 1297. Copyright (2006) American Chemical Society.)...

W. Li, M. Zhu, Q. Zhang, and D. Chen, Expanded conformation of macromolecular chain in polyaniline with one-dimensional nanostructure prepared by interfacial polymerization, Appl. Phys. Lett., 89, 103110 (2006). 

Joshi et al., in Chapter 2, Self-assembled nanostructure preparation and applications, discuss about the fabrication of nanostructures from biological building blocks. The self-assembly of such nanostructures is a spontaneous process by which molecules/nanophase entities will materialize into organized aggregates. Many biomolecules, such as proteins and peptides, can interact and self-assemble into highly ordered supramolecular architectures including nanotubes, nanofibrils, nanowires, spherical vesicles, and hybrids, the subsequent improvement of their properties and their possible applications. 

J. J. Kelly, D. Vanmaekdhergh, Porous-etched Semiconductors Formation and Characterization, in The Electrochemistry of Nanostructures Preparation and Properties, Chap. 4 (Eds. G. Hodes), Wiley-VCH, Weinheim, 2001. 

Concerning the preparation techniques, there are different approaches from vapor or liquid phase. The critical aspects, that have to be taken into account, are the reliability of the preparation process, the quality of the nanostructures prepared and the integration into final devices. Among the most promising techniques there are catalyst assisted vapor phase transport and thermal oxidation. Vapor phase technique consists in the evaporation of the oxide powder in a furnace with controlled atmosphere. In general the pressure is lower than lOOmbar to ease the vaporization of the oxide powder and an inert gas carrier is used to facilitate the mass transport from the source to the substrates, where the vapors condense in form of nanowires. 

Martin [21] proposed a mechanism for the growth of the nanostructures prepared by the hard-template method. However, the mechanism is insufficient in explaining the growth of partially filled nanotubes by an electrochemical template synthesis [36]. Recently, Lee and coworkers [37] investigated the electrochemical... 

Bmst, M., Kiely, C. J. (2002). Some Recent Advances in Nanostructure Preparation from Gold and Silver Particles A Short Topical Review. glJgj g jj Sirfaceg Physicochemical and Engineering Aspects. 202t2). 175-186. 

Hybrid composites using natural polymer blends and carbon nanostructures preparation, characterization, and applications... 

Alikhanzadeh-Arani, S. and Salavati-Niasari, M. (2012) Synthesis and characterization of high-temperature ceramic YBCO nanostructures prepared from a novel precursor. /. Nanostruct, 1, 62-68. 

Dong, E, Zhao, W. Wu, Z. Characterization and photocatalytic activities of C, N and S co-dopedTi02 with ID nanostructure prepared by the nano-confinement effect. Nanotechnology 19 36 (2008), 365607. 

Functional Polymeric Nanostructures Prepared by Self-Assembly and Beyond... 

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