Nanostructured particles

Madler L, Kammler HK, Mueller R, Pratsinis SE (2002). Controlled synthesis of nanostructured particles by flame spray pyrolysis. J Aerosol Sci 33 369 -388... 

Shu, S., Husain, S. and Koros, W.J. (2007) A general strategy for adhesion enhancement in polymeric composites by formation of nanostructured particle surfaces. Journal of Physical Chemistry C, 111 (2), 652-657. 

Abstract. IR pyrolysis of PAN and PAN based composites yields ordered graphitelike structure as well as several carbon nanostructures. Metal-carbon nanocomposites, in which the nanosized metal particles were introduced into the structure of carbon matrix in the course of IR pyrolysis of composite-precursor on the basis of PAN and metal (Gd, Pt, Ru, Re) compounds were prepared. The carbon phase of metal-carbon nanocomposites was shown to include different types of nano structured carbon particles. Bamboo-like CNT were observed in the structure of pyrolized at 910 and 1000°C composite-precursor based on PAN and GdCl3. At T=1200°C the solid carbon spheres with diameter in the range of 50-360 nm and octahedral carbon particles with the size in the range of 300-350 nm were observed. These nanostructured particles consist of carbon only or they include Gd nanoparticles incapsulated in carbon shell. IR pyrolysis of composite-precursor based on PAN as well as H2PtCl6 and RuC13 or NH4Re04 (Pt Ru(Re)=10 l) allows the preparation of Pt-Ru and Pt-Re alloys nanoparticles with 2[Pg.577]

It is important to note that structural transformations of obtained bamboo-like CNT takes place while IR radiation intensity rises. At T=1200°C bamboo-like CNT are converted to solid carbon spheres with diameter in the range of 50-360 nm and octahedral carbon particles with the size in the range of 300-350 nm (Fig. 5). These nanostructured particles consist of carbon only or they contents Gd nanoparticles incapsulated in spherical or octahedral carbon particles. The mechanism of high temperature structural transformations of bamboo-like CNT still needs research. 

Nanostructured particles are easily produced by sonochemically treating volatile organometallic precursors. The powders formed are usually amorphous, agglomerated, and porous. To get the crystalline phases, these powders must be further annealed however, this annealing temperature is lower than that needed... 

Figure 1.3. (A) Photographs of silver island films (SIFs) deposited onto glass and plastic supports. (B) Normalized absorbance of zinc, copper, gold and silver nanostructured particles on a glass support. Atomic force microscope images of SIFs on (C) glass (D) plastic support.

Tlie CVD method is usually used to produce a thin film material which is formed on a heated substrate. However, nanostructured particles of ceria and ceria-yttria have been synthesized by some arrangements of the apparatus. Figure 3.8 shows the schematic CVD reactors for synthesizing ceria-based nanopanicles.Two types of rector has been presented. The nanoparticles are collected either on a cooled quartz susceptor (A) that is in a furnace, or in a cold wall container outside the furnace (B), The precursor cerium chloride set on the container is evaporated and... 

This process produces stabilized highly porous amorphous nanostructured particles with improved wetting and rate of dissolution. The crystallinity can be tuned by varying the processing solvents, stabilizers, and conditions. Drug loading has been reported to be as high as 91%.[ l... 

Similar studies in an organic solvent yielded almost the same product [66]. Nanostructured particles of amorphous carbon-activated palladium metallic clusters have been prepared (in situ) at room temperature by ultrasound irradiation of an organometallic precursor, tris-//-[dibenzylideneacetone]dipalladium [(p-CH= CH-CO-CH=CH-5 )3Pd2] in mesitylene. Characterization studies show that the product powder consists of nanosize particles, agglomerated in clusters of approximately 800 A. Each particle is found to have a metallic core, covered by a carbonic shell that plays an important role in the stability of the nanoparticles. The catalytic activity in a Heck reaction, in the absence of phosphine ligands, has been demonstrated. 

Fauchais, P., Montavon, G., Lima, R.S., and Marple, B.R. (2011) Engineering a new class of thermal spray nano-based microstructures from agglomerated nanostructured particles, suspensions and solutions an invited review. /. Phys. D Appl. Phys., 44 (9), 093001. 

The structure, microstructure, and properties of these composite materials have been studied by X-Ray diffraction, AFM, TEM, and electrical measurements. Anticipated applications of the present composites are photanodes for hydrogen production, active lithium-ion rechargeable battery materials, and chemical gas sensors. An important aspect of these composite materials is the nature of the interfacial properties of the nanostructured particles and the PPX material. 

It has been reported that Y2O3 nanoparticles as-prepared by gas phase synthesis have the monoclinic stmcture of high pressure phase, which transforms into cubic Y2O3 above 873 K [7,8]. It has been elucidated from the dependence of the phase transition temperature on the state of compaction that the stability of the high pressure phase is due to the nanostructured particle size. 

Reaction Vessels Assembled by the Sequential Adsorption of Polymers 4.2.1 Microreactors from Nanostructured Particle Templates... 

THF are miscible). Then the good-solvent THF which has a higher vapor pressure than water was allowed to slowly evaporate. Due to the fact that neither of the two copolymer blocks is water soluble, droplets with a high polymer and THF concentration form which Anally form colloids when all the THF has evaporated. Then, the PLA phase was selectively removed by the addition of NaOH and methanol. The nanostructured particles were then collected by centrifugation, dispersed on a substrate, and characterized by means of SEM, see Fig. 4.22. Adjusting the polymer concentration and the THF water ratio allows to control the formed particle size. 

X. Zhang, M. Oulad-Abdelghani, A.N. Zelkin, Y. Wang, Y. Haikel, D. Mainard, et al.. Poly (L-lysine) nanostructured particles for gene dehvery and hormone stimulation, Biomaterials 31 (2010) 1699-1706. 

Iskandar, F., Gradon, L., Okuyama, K., 2003, Control of morphology of nanostructured particles prepared by the spray drying of a nanoparticle sol, J. Colloid Interface Sci. 265, 296-303. 

Okuyama K, Abdullah M, Lenggoro IW, Iskandar F (2006) Preparation of functional nanostructured particles by spray drying. Adv Powder Technol 17 587-611... 

Thus, the titanium nitride powder in the halide-sodium azide system is synthesized in the form of nanostructured particles. They can have a nanofiber structure with fibers 50-100 nm in diameter and a nanocrystalline structure with an average crystallite size of 100-200 nm. 

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