Nanoparticles growth

Lacroix, L.M., Lachaize, S., Falqui, A., Respaud, M. and Chaudret, B. (2009) Iron nanoparticle growth in organic superstructures. Journal of the American Chemical Society, 131 (2), 549-557. 

Carrageenans and alginates present different conformations egg-box structure (alginates) and double helices (carrageenan) but both natural biopolymers are able to form gels and consequently, to control nanoparticle growth. 

Fig. 5.22 (A-D) Scheme of Au nanoparticle growth between bilayers (A) nucleation at bilayer interfaces and bulk-like growth when particle size is smaller than the lamellar d spacing (B) once the transversal particle size is larger than the d spacing, growth is slowed by the bilayers, the transversal Au3+flux being limited, leadingto elongated particles shapes (C) when the constraint exerted by the particles on the bilayers is...

El-Rassy, H., Belamie, E., Livage, J. and Coradin, T. (2005) Onion phases as biomimetic confined media for silica nanoparticle growth. Langmuir, 21, 8584-8587. 

Mirkin CA, Jin R, Gao YC, Hao E, Metraux GS, Schatz GC (2003) Controlling Anisotropic Nanoparticle Growth Through Plasmon Excitation. Nature 425 487-490... 

Dendrimers are a special class of arborescent monodisperse nanometer sized molecules that have been used in the synthesis of Au NPs as surface stabilizers or nanoreactor/templates for nanoparticle growth. Moreover, these hybrid nanomaterials have great potential for application in different fields such as sensors, imaging in cells, electrooptical devices, catalysis, drug delivery agents, and so on. 

Pong, B. K., Elim, H. I., Chong, J. X., Ji, W., Trout, B. L., Lee, J. Y., New insights on the nanoparticle growth mechanism in the citrate reduction of Gold(III) salt Formation of the au nanowire intermediate and its nonlinear optical properties. Journal of Physical Chemistry C2007, 111, 6281-6287. 

Oatway, L., Vasanthan, T. and Helm, J.H. 2001. Phytic Acid. Food Res. Intemat., 17, 419—431. Orecchioni, A.-M., Duclairoir, C., Renard, D. and Nakache, E. 2006. Gliadin Characterization by Sans and Gliadin Nanoparticle Growth Modelization. J. Nanosci. Nanotechnol., 6, 3171-3178. 

This argument shows that the processes used for the production of very small particles must be carefully controlled in order that a minimum number of additional defects is introduced. Various sophisticated processes have been developed which allow nanoparticles to be prepared, showing more less controlled nanostructures. These processes may involve size reduction of larger particles (top-down approach) or direct nanoparticle growth (bottom-up approach). The most important of these processes are described in the following sections. 

Figure 4.4.1 Schematic representation of the model systems discussed within the chapter (A) nanoparticle growth influenced by dopants in the support, (B) nanoparticle deposition from solution, (C) strong metal support interaction, and (D) photochemistry at supported nanoparticles as a function of size.

Averitt, R. D. (1997), Plasmon resonance shifts of Au-coated Au2S nanoshells Insight into multicomponent nanoparticle growth, Phys. Rev. Lett., 78,4217 220. 

Jin, R., et al. (2003) Controlling anisotropic nanoparticle growth through plasmon excitatioa Nature 425 487-90. 

It was found that PVP was essential for stable nanoparticle growth and indeed it is claimed in reference [89] that PVP preferentially binds to the 111 faces, thus directing growth in the 100 direction. It should be noted that this implies a reversal of the behaviour of PVP, which normally preferentially bind to 100 faces. It is also... 

PECULIARITIES OF NANOPARTICLES GROWTH IN LOW PRESSURE SPRAY PYROLYSIS... 

A mathematical model of a nanoparticles growth during evaporation of a micron size droplet in a low pressure aerosol reactor is developed. The main factor is found to be evaporating cooling of droplets which affects formation of supersaturated solution in the droplet. The rate of cooling can reach 2T0 K/s. The final radius of nanoparticles was found to be independent on the precursor radius. Manifestation of Lifshitz-Slezov instability is illustrated by experimental data. Effects of Brownian motion of nanoparticles inside the droplet are discussed. 

Noteworthy, the characteristic time of the nanoparticles growth is much larger than the characteristic time of evaporative cooling of the droplet. It is also clear that the number of precursors in the droplet is an important parameter which indeed affects the final radii of nanoparticles. Our calculations show that the precursor radius does not affect on the final radius of a nanoparticle. 

Stopped or continuous flow reaction methods can be utilized with synchrotron-based SAXS measurements to determine reaction kinetics, including protein folding, nanoparticle growth, breakdown, and aggregation. Using a synchrotron X-ray source, the SAXS spectrum can be collected with a one or two dimensional detector with good quality in periods as short as 0.001 s. 

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