Laser-assisted synthesis

Plasma-jet diamond techniques yield growth rates of about 980 p.m/h (163,164). However, the rate of diamond deposition is still one to two orders of magnitude lower than the HP—HT technology, which is about 10,000 p.m/h (165). Diamond deposition rates of ca 1 p.m/s have been reported usiag laser-assisted techniques (166). This rate is comparable to the HP—HT synthesis. 

Bondi, S. N., et al. (2006), Laser assisted chemical vapor deposition synthesis of carbon nanotubes and their characterization, Carbon, 44,1393-1403. 

In the case of hot-filament CVD, refractory metal filaments (e.g., W, Ta, Re, etc.) are electrically heated to very high temperatures (between 2000 and 2700°C) to produce the necessary amount of atomic hydrogen that is necessary for the reasons mentioned above for the synthesis of diamond. Except for combustion flame CVD, hot-filament CVD is considered the simplest of all of the methods and also the most inexpensive. Plasma-jet and laser-assisted CVD methods rely on a plasma torch or laser to attain the very high temperatures that are needed to... 

LASER AND PLASMA ASSISTED SYNTHESIS OF COMPOSITE NANOPARTICLES IN LIQUIDS... 

Si Laser-assisted catalytic growth, laser ablation, catalytic growth, HT synthesis, thermal evaporation SiO, CVD [141,142]... 

Aithal, S.M., Subramaniam, V (2002), Laser-Assisted and Optical Pumping Techniques for Diamond Synthesis, in Diamond Films Handbook, Asmussen, I, and Reinhard, D. (eds.), Marcel Dekker, New York. 

Pyatenko, A., 2010. Synthesis of Silver Nanoparticies with Laser Assistance. In-Tech, Rijeka. 

F. T. Wallenberger, Inorganic fibers and microfabricated parts by laser assisted CVD synthesis and phase transformations, in Novel Techniques in Synthesis and Processing of Advanced Materials, J. Singh and S. M. Copley, eds., The Metals and Materials Society, pages 251-260 (1995). 

Recent research work by Museur et al. showed UV-laser-assisted nucleation of boron nitride nanorods from hexagonal boron nitride (h-BN). Pallets of h-BN powder were used as the target compound for the synthesis and they were subjected to a UV-laser irradiation in their ablation regime for laser pulse duration in picoseconds domain. The ambient gas pressure was kept relatively high (above 500 bar) and oxygen pressure was below 0.2 mbar. The appearance of the nanorods was noticed typically with the pulse duration of 5 ps or shorter. 

C.A. Crouse, E. Shin, P.T. Murray, J.E. Spowart, Solution assisted laser ablation synthesis of discrete aluminum nanoparticles. Mater. Lett. 64, 271-274 (2010)... 

There are no obstacles in searching for novel approaches to diamond synthesis by studying new growth processes electrolysis, hydrothermal (15) and laser assisted. Graphite has been transformed to diamond by laser process (16,17) and some laser assisted CVD processes were... 

The use of diisoprop anolamine in the synthesis of the hyperbranched poly-esteramide resins has led to defined molecules according to the predicted structures (Fig. 7) as confirmed by MALDI-TOF (Matrix Assisted Laser Desorption Ionization - Time Of Flight) and ESI (Electro Spray Ionization) mass spectra... 

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