Synthesis and Coating of Aluminum NanoCrystals

ABSTRACTWe show a low temperature gas-phase synthesis route to produce faceted aluminum crystals in the aerosol phase. Use of triisobutylaluminum whose decomposition temperature is below the melting point of elemental aluminum enabled us to grow nanocrystals from its vapor. Combustion tests show an increase in energy release compared to commercial nanoaluminum. Production of aluminum in an oxygen free environment resulted in a bare aluminum surface that was passivated in separate experiments with nickel and iron by decomposition of their carbonyl precursors.

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Perchlorosilanes and Perchlorocarbosilanes as Precursors to Silicon Carbide

MRS Proceedings ◽

10.1557/proc-0911-b05-12 ◽

2006 ◽

Vol 911 ◽

Author(s):

Vladimir Sevastyanov ◽

Yurij Ezhov ◽

Roman Pavelko ◽

Nikolaj Kuznetsov

Keyword(s):

Thermal Decomposition ◽

Silicon Carbide ◽

Low Temperature ◽

Gas Phase ◽

Thermodynamic Modeling ◽

Reaction System ◽

Reaction Products ◽

Gaseous Species ◽

Phase Synthesis ◽

Key Features

AbstractHomologues with the general stoichiometry a(SiCl4) : bSi : cC : d(SiC) are shown to be potential precursors for the low-temperature gas-phase synthesis of silicon carbide. Thermal decomposition of these precursors yields the chemically stable gaseous species SiCl4 and condensed Si, C, SiC, SiC+Si, or SiC+C. Thermodynamic modeling of the thermal decomposition of octachlorotrisilane, Si3Cl8, is used to analyze the key features of the thermolysis of perchlorosilanes with the general stoichiometry a(SiCl4) : bSi. The equilibrium compositions of reaction products in the Si3Cl8+CO system are determined. This reaction system enables low-temperature (400 – 1200 K) synthesis of silicon carbide.

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The Gas-Phase Synthesis of a New Functional Hybrid Material on the Basis of Multiwalled Carbon Nanotubes Decorated with Faceted Aluminum Nanocrystals

Technical Physics Letters ◽

10.1134/s1063785018100085 ◽

2018 ◽

Vol 44 (10) ◽

pp. 865-868 ◽

Cited By ~ 5

Author(s):

K. V. Kremlev ◽

A. M. Ob”edkov ◽

N. M. Semenov ◽

B. S. Kaverin ◽

S. Yu. Ketkov ◽

...

Keyword(s):

Carbon Nanotubes ◽

Gas Phase ◽

Multiwalled Carbon Nanotubes ◽

Hybrid Material ◽

Multiwalled Carbon ◽

Phase Synthesis ◽

Gas Phase Synthesis ◽

Aluminum Nanocrystals

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Application of a novel gas phase synthesis approach to carbonyl complexes of accelerator-produced 5d transition metals

Radiochimica Acta ◽

10.1515/ract-2021-1028 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Michael Götz ◽

Alexander Yakushev ◽

Stefan Götz ◽

Antonio Di Nitto ◽

Christoph E. Düllmann ◽

...

Keyword(s):

Gas Phase ◽

Carbonyl Complex ◽

Carbonyl Complexes ◽

Tandem Accelerator ◽

Phase Synthesis ◽

Novel Approach ◽

Series Of Experiments ◽

Low Efficiency ◽

Free Environment ◽

Synthesis Approach

Abstract In 2014 the first synthesis of a transactinide carbonyl complex – seaborgium hexacarbonyl – was reported. This was achieved in gas-phase chemical experiments in a beam-free environment behind the recoil separator GARIS. Extending this work to heavier elements requires more efficient techniques to synthesize carbonyl complexes as production rates of transactinide elements drop with increasing atomic number. A novel approach was thus conceived, which retains the benefit of a beam-free environment but avoids the physical preseparation step. The latter reduces the yields for products of asymmetric reactions such as those used for the synthesis of suitable isotopes of Sg, Bh, Hs and Mt. For this a series of experiments with accelerator-produced radioisotopes of the lighter homologues W, Re and Os was carried out at the tandem accelerator of JAEA Tokai, Japan. A newly developed double-chamber system, which allows for a decoupled recoil ion thermalization and chemical complex formation, was used, which avoids the low-efficiency physical preseparation step. Here, we demonstrate the feasibility of this newly developed method using accelerator-produced short-lived radioisotopes of the 5d homologues of the early transactinides.

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