A POSSIBLE MECHANISM OF NANODIAMOND
A POSSIBLE MECHANISM OF NANODIAMOND
Detonation nanodiamond - Wikipedia
Traditional detonation nanodiamond applications include metal-diamond galvanic coatings, polishing pastes and suspensions, polymer composities, lubricating oils, greases and lubricant-coolants. Novel detonation nanodiamond niche applications developed recently include DND for systems of magnetic recording, adsorbent of a new type, as a component in the production of diamond ceramics and moulds made of diamond-containing materials, as coatings in field emission devices, catalyzes of heterogeneous and electrochemical catalysis, in proton-conducting nanocomposite membranes in fuel cells applications. DND had also been employed for seeding substrates used in the CVD growth of diamond films. Preliminary investigation demonstrated that DND is non-toxic and biocompatible, that make it attractive for bio-applications taking into account its rich surface chemistry that can be modified in a controllable way.
MST-ND is nanodiamond powder obtained by the unique technology using laser treatment of specially prepared targets containing carbon soot and hydrocarbons in liquid media.
detonation-synthesis nanodiamond ..
There is a special class of nanodiamond material called 'ultra-nanocrystalline' diamond (or 'ultra-dispersed' diamond) with the characteristic size of the basic diamond constituents encompassing the range of just a few nanometers to distinguish it from other diamond-based nanostructures with characteristic sizes above ~10nm. Within this class of the materials, very attractive for the nearest future nanotechnological applications are ultrananocrystalline particles produced by detonation of carbon explosive materials (characteristic size of primary particles ~ 3-6 nm) developed in the former USSR in the 60-s. The nanodiamond synthesized from carbon contained in the molecules of explosives by the detonation of the explosive is often called nanodiamond of detonation origin or detonation nanodiamond [1-4]. This class of nanodiamond material is technologically important since detonation nanodiamond can be produced in bulk quantities.
In our research we pursue applications based on nanodiamond of detonation origin, including field emission devices, nanocomposites for microelectronics as well as bioapplications.
A Novel Technique for the Synthesis of Nanodiamond …
Abstract—A new mechanism of formation of nanodiamond particles during detonation synthesis has been put forward. It includes the following steps: (a) decomposition of trinitrotoluene (TNT) molecules into basic radicals—a radicallike dimer C2 and CO3, decomposition of hexogen molecules into C2 and of benzotrifuroxane molecules into C2; (b) formation of cyclohexane from C2 or immediately of radical adamantane molecules; (c) interaction of diamondlike core (adamantane radical) with methyl and other monocarbon radicals; and (d) growth of detonation nanodiamond particles like in a CVD process. It is shown that the nucleation of a radicallike adamantine molecule occurs within a range between the center of the chemical peak zone and the ChapmanJouguet plane, the growth of diamond particles takes place at the same time and comes to an end at an early stage of isoentropic (Taylor) expansion of detonation gases entrapping solid carbon particles.
The theory of the process giving rise to detonation nanodiamond (DND) particles is still a matter of discussion and, in our opinion, there is no adequate physicochemical model of detonation synthesis. Nevertheless, the data obtained by ourselves and other scientists during the experiments involving the blasting of a TNT–hexogen compound (about 50/50) and hydrogenfree benzotrifuroxane enable one to come to a better understanding of the mechanism of DND formation.
an explosive detonation synthesis nanodiamond
Global Detonation Synthesis Nanodiamond Powder …
Detonation nanodiamond ..
Global Detonation Synthesis Nanodiamond Powder Market …
Nanodiamond - Wikipedia
Ultrasonic Synthesis of Nanodiamonds - Hielscher
Atmospheric-pressure chemical purification of detonation-synthesized nanodiamond by using ..
Detonation synthesis nanodiamond powder global ..
Analysis of the time dependence of RDP shows that the diamond formation started in CRZ goes on also beyond this zone. Thus, we may consider it a proved fact that the process of nanodiamond formation occurs in CRZ and is over at the beginning of Taylor expansion of DPs, i.e., as DPs scatter, the DND crystallites ini tially grow and stop growing only after an abrupt drop of pressure and temperature and a decrease in concen tration of active carbon radicals. In general, the parameters of the onset and completion of DND formation processes were determined. The location of DND formation is adequately definite, while it is still unclear what from and how an DND crystallite arises and why the crystallite stops growing.
Nanodiamonds powder of laser synthesis without …
Apparently, there are more than one mechanisms of DND formation. The formation of primary fragments of future nanodiamonds from hydrocarbon radicals starts from the center to the end of the chemical reaction zone (up to the ChapmanJouguet plane). As this takes place, there forms not a benzene nucleus but, probably, cyclohexane (which is energetically more favorable). A small amount of liquid carbon droplets formed from hexogen or BTF by the liquid droplet coalescence mechanism are crystallized or become amorphous as the gaseous DPs expand during an early stage of their expansion (at the first stage of isoentropic curve).
Detonation Synthesis Nanodiamond Powder Market - …
The history of the discovery of nanodiamond synthesis, the investigation of nanodiamond properties, and the application and organization of their production in the second half of the 20th century is expounded. It is noted that this history is unique, since nanodiamond synthesis was discovered in the USSR three times over 19 years: first by K.V. Volkov, V.V. Danilenko, and V.I. Elin at the VNIITF (Snezhinsk) in 1963 and then, in 1982, by A.M. Staver and A.I. Lyamkin at the Institute of Hydrodynamics, Siberian Division, Academy of Sciences of the USSR (Novosibirsk), and by G.I. Savvakin at the Institute of Problems of Materials Science, Academy of Sciences of the UkSSR (Kiev). All of these researchers discovered nanodiamond synthesis accidentally while studying diamond synthesis by shock compression of nondiamond carbon modifications in blast chambers. The priority of work by Russian scientists in this field is demonstrated.
Detonation Synthesis Nanodiamond Powder Market …
A study of the isotope composition of diamondcontaining soot produced by detonation of an octogen– TNT mixture was carried using an C13 tracer isotope in a methyl group and revealed that during the detonation synthesis the major portion of DND is formed from carbon included in the TNT composition . A similar conclusion was made upon an investigation of the process of synthesis from the hexogen–TNT mixture by using 14C tracer in the first position of benzene ring of TNT [16–20]; in this case, all carbon atoms of TNT are involved in the diamond formation. In detonation of the TNT–hexogen mixture (50/50) nanodiamonds are formed from TNT and hexogen carbon in the ratio 93/7, respectively.
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