Nanocarbon particle size

The greatest advantage of in situ methods over ex situ processes is the benefit of using the nanocarbon as a substrate, template and heat sink for stabilizing metastable phases and small particle sizes and creating hybrids with unusual morphologies [232]. This enables the synthesis of new hybrid materials that may offer new properties and unknown potential for future research and application. 

There are various experimental ways for obtaining multilayer nanoparticles on the nanocarbon basis modified by silver and a water-soluble poly-vinylpyrrolidoneshell. The following scheme seems to be the most e q)e-dient for possible regulating the particle sizes of the reduced silver and polyvinylpyrrolidone coating on the received nanoparticles ... 

Polypropylene (PP) Kaplen of mark 01030 with average weight molecular mass of - (2-3) X10 and polydispersity index 4.5 was used as a matrix polymer. Nanodimensional calcium carbonate (CaCOj) in a compound form of mark Nano-Cal P-1014 (production of China) with particles size of 80 nm and mass contents of 1-7 mass % and globular nanocarbon (GNC) (production of corporations group United Systems, Moscow, Russian Federation) with particles size of 5-6 mn, speeifie surfaee of 1400 mVg and mass contents of 0.25-3.0 mass % were applied as nanofiller. 

Carbon occurs in many forms, and their properties, depending on each form of its special structure, make carbon a truly unique building block for nanomaterials. Nanocarbon materials are defined so that not only is their primary particle size on a nanometer scale, but also their structures and/or textures are controlled on a nanometer scale [1]. Either the nanosize or nanostructure of the carbon materials have to be deliberately controlled to govern their properties and functions [2], In the last two decades, novel... 

Nanocarbons—carbon materials that have particle sizes less than about 100 nm. Three types of nanocarbons that can exist are as follows ... 

For application in flow reactors the nanocarbons need to be immobilized to ensure ideal flow conditions and to prevent material discharge. Similar to activated carbon, the material can be pelletized or extruded into millimeter-sized mechanically stable and abrasion-resistant particles. Such a material based on CNTs or CNFs is already commercially available [17]. Adversely, besides a substantial loss of macroporosity, the use of an (organic) binder is often required. This material inevitably leaves an amorphous carbon overlayer on the outer nanocarbon surface after calcination, which can block the intended nanocarbon surface properties from being fully exploited. Here, the more elegant strategy is the growth of nanocarbon structures on a mechanically stable porous support such as carbon felt [15] or directly within the channels of a microreactor [14,18] (Fig. 15.3(a),(b)), which could find application in the continuous production of fine chemicals. Pre-shaped bodies and surfaces can be... 

It should also be briefly recalled that semiconductors can be added to nanocarbons in different ways, such as using sol-gel, hydrothermal, solvothermal and other methods (see Chapter 5). These procedures lead to different sizes and shapes in semiconductor particles resulting in different types of nanocarbon-semiconductor interactions which may significantly influence the electron-transfer charge carrier mobility, and interface states. The latter play a relevant role in introducing radiative paths (carrier-trapped-centers and electron-hole recombination centers), but also in strain-induced band gap modification [72]. These are aspects scarcely studied, particularly in relation to nanocarbon-semiconductor (Ti02) hybrids, but which are a critical element for their rational design. 

The synthesis of a Fe/carbon/LiF nanocomposite was performed by pyrolysis of a pre-milled ferrocene/LiF mixture in an autoclave. The treatment led to the formation of 5-20 nm sized Fe nanoparticles which were intimately embedded in multi-walled nanocarbon structures. HR-TEM studies showed that the particles were encapsulated in onion-like graphite layers which were partly defective (Fig. 3.10). LiF was in close vicinity to the iron and physisorption analysis revealed that the composite possesses an... 

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