Gas phase pyrolysis synthesis of carbon nanotubes at high temperature

The aim of the study is to develop information systems for supporting and supporting decision-making in the production of a metal oxide catalyst that provides targeted synthesis of carbon nanotubes by gas-phase chemical deposition. To achieve the goal, the following tasks were solved: a new approach to the process of creating a catalyst for the thermal decomposition of unstable compounds for synthetic nanotubes was developed; experimental studies of the effect on the post-thermal treatment of the catalyst and its precursors by physical action (ultrasonic, electromagnetic and microwave fields, etc.), which were obtained the approximating characteristics of the synthesized models of carbon nanostructures on the parameters of the process of pre- and post-thermal treatment of the catalyst were used to create a recommendation module. On the basis of the results obtained, blocks of implementation and technologies were developed, used in the creation of a system for maintaining and supporting solutions for the production of a catalyst for synthetic nanotubes. The application of the developed system of maintenance and support of decisions makes it possible to form a catalyst that makes it possible to synthesize carbon nanotubes with specified characteristics. Also, the use of this information system in the production of a catalyst helps to expand the range of synthesized nanoproducts in the process of gas-phase chemical deposition without changing the composition of the catalyst.

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Methods for the chemical synthesis of carbon nanotubes: an approach based on hemispherical polyarene templates

Pure and Applied Chemistry ◽

10.1515/pac-2016-1222 ◽

2017 ◽

Vol 89 (6) ◽

pp. 809-820 ◽

Cited By ~ 5

Author(s):

Lawrence T. Scott

Keyword(s):

Carbon Nanotubes ◽

Gas Phase ◽

Large Diameter ◽

Small Diameter ◽

Diels Alder ◽

Promising Candidate ◽

Benzene Rings ◽

End Caps ◽

Synthesis Of Carbon Nanotubes ◽

Walled Carbon Nanotubes

AbstractHemispherical polyarenes represent attractive templates from which carbon nanotubes of the same diameter and rim structure (chirality) might be grown by repetitive annulation reactions. The resulting single-index (n,m) nanotubes would have one end open and the other end capped by the original template. Efforts in the author’s laboratory to synthesize (5,5) and (6,6) nanotube end-caps are described. Nitroethylene is shown to serve well as a “masked acetylene” for the conversion of polyarene bay regions into new unsubstituted benzene rings by a Diels-Alder cycloaddition/aromatization process. Benzyne reacts similarly, both in solution and in the gas phase. These annulation reactions are proposed as methods for elongating large-diameter templates that have bay regions on their rims into structurally uniform, single-walled carbon nanotubes. Unfortunately, the bay regions on the strongly curved rim of the small-diameter (5,5) nanotube end-cap 3 resist Diels-Alder cycloadditions with both nitroethylene and benzyne. Pentabenzocorannulene (14) is proposed as a promising candidate for surface-catalyzed cyclodehydrogenation to a surface-bound hemispherical polyarene that could serve as a template for synthesis of pure (5,5) carbon nanotubes.

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