Novel ultrahard carbon structures by cold-compressing tubes

CrystEngComm ◽  
2021 ◽  
Vol 23 (10) ◽  
pp. 2091-2098
Author(s):  
Kuo Hu ◽  
Ran Liu ◽  
Zhen Yao ◽  
Yuan-Yuan Liu ◽  
Yuan-Yuan Wang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Dft Theory ◽  
Topological Structures ◽  
Carbon Structures

Four novel superhard carbon structures named L-, CM-, and K-carbon and Cco-C160 are proposed by cold-compressing carbon nanotubes based on DFT theory, which adopt the 5 + 6 + 7, 5 + 6 + 8, 6 + 14 and 4 + 6 + 8 topological structures, respectively.

Thermal-CVD System Designed for Growth of Carbon Nanotubes

2006 ◽  
Author(s):  
Samuele Porro ◽  
Simone Musso ◽  
Massimo Rovere ◽  
Mauro Giorcelli ◽  
Angelica Chiodoni ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Chemical Vapor ◽  
Nitrogen Atmosphere ◽  
Metal Catalyst ◽  
Silicon Substrates ◽  
Carbon Structures ◽  
High Temperature Furnace ◽  
Aligned Carbon Nanotubes ◽  
Growth System ◽  
Vertically Aligned

We report a study on a thermal chemical vapor deposition (CVD) system optimized for the growth of well packed and vertically aligned carbon nanotubes (CNTs) on uncoated silicon substrates. The process of synthesis involves the co-evaporation of a carbon precursor and a metal catalyst in a nitrogen atmosphere inside a high temperature furnace. Beside the formation of CNTs, depending in particular on the deposition temperature, other carbon structures can be deposited, such as nanographite. We show the growth results analyzed by different characterization techniques (electron microscopy, porosity and thermal stability investigations, micro-Raman spectroscopy). In addition, we report an investigation on the development of secondary transversal vortex flows caused by the effects of distribution of temperatures inside the growth system, in order to correlate them with the growth results.

scholarly journals CARBON STRUCTURES AS EFFECTIVE MODIFIERS OF THE MATERIALS’ BASIC PROPERTIES

2017 ◽  
Vol 5 ◽  
pp. 1135-1142
Author(s):  
Natalia Kamanina
Keyword(s):  
Carbon Nanotubes ◽  
Quantum Dots ◽  
Refractive Index ◽  
Optical Properties ◽  
Second Harmonic ◽  
Inorganic Materials ◽  
Mechanical Parameters ◽  
Ir Laser ◽  
Carbon Structures ◽  
Spatial Frequencies

Because of the unique energetic, refractive and photoconductive characteristics of effective nano-objects, especially carbon nanotubes, the modification of optical properties of the organic and inorganic materials can be considered as the preferable one via the use of the nanostructuration process. Emphasis has been given to the incorporation of nanoobjects directly in the materials’ body and on their surface. Under the conditions of a surface treatment of the inorganic structures, an IR-laser at the wavelength of 10.6 micrometers was used to orientate carbon nanotubes deposited in the electric field of 100-600 V×cm-1. Dramatic spectral and mechanical parameters changes have been found. Refractive features of the nanostructured organics have been studied via applying the second harmonic of the pulsed Nd-laser at different spatial frequencies and under the nanoparticles sensitization doping such as fullerenes, carbon nanotubes, shungites, quantum dots, and graphenes. A drastically obtained laser-induced refractive index has been established. A prediction has been proposed to extend the area of the application of the systems considered.

Catalytic conversion of propan-2-ol and butan-2-ol on carbon nanotubes with different carbon structures

2020 ◽  
Vol 30 (3) ◽  
pp. 355-358
Author(s):  
Evgeniya A. Tveritinova ◽  
Yurii N. Zhitnev ◽  
Ekaterina A. Arkhipova ◽  
Sergey A. Chernyak ◽  
Anton S. Ivanov ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Catalytic Conversion ◽  
Carbon Structures

Efficient oxygen reduction catalysts formed of cobalt phosphide nanoparticle decorated heteroatom-doped mesoporous carbon nanotubes

2015 ◽  
Vol 51 (37) ◽  
pp. 7891-7894 ◽  
Author(s):  
Kuiyong Chen ◽  
Xiaobin Huang ◽  
Chaoying Wan ◽  
Hong Liu
Keyword(s):  
Carbon Nanotubes ◽  
Oxygen Reduction ◽  
Mesoporous Carbon ◽  
Carbon Nanostructures ◽  
Catalytic Performance ◽  
Electronic Interaction ◽  
Cobalt Phosphide ◽  
Carbon Structures ◽  
Oxygen Reduction Catalysts ◽  
Reduction Catalysts

Co2P nanoparticles could strongly promote the ORR catalytic performance of the heteroatom-doped carbon nanostructures via the electronic interaction between the embedded Co2P nanoparticles and the heteroatom-doped carbon structures.

scholarly journals Melamine as a single source for fabrication of mesoscopic 3D composites of N-doped carbon nanotubes on graphene

RSC Advances ◽  
2018 ◽  
Vol 8 (22) ◽  
pp. 12157-12164 ◽  
Author(s):  
Xiao-Ling Yan ◽  
Hua-Fei Li ◽  
Chen Wang ◽  
Bang-Bang Jiang ◽  
Hai-Yan Hu ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Two Dimensional ◽  
Single Source ◽  
One Dimensional ◽  
Carbon Structures ◽  
Enhanced Properties

Integration of two-dimensional graphene and one-dimensional carbon nanotubes (CNTs) to create potentially useful 3D mesoscopic carbon structures with enhanced properties relative to the original materials is very desirable.

Atomic Force Microscopy of Carbon Nanotubes and Nanoparticles

1994 ◽  
Vol 359 ◽  
Author(s):  
Ping Li ◽  
Klaus Satftler
Keyword(s):  
Carbon Nanotubes ◽  
Atomic Force Microscopy ◽  
Pyrolytic Graphite ◽  
Graphite Substrate ◽  
Spherical Type ◽  
Carbon Vapor ◽  
Force Microscopy ◽  
Sapphire Substrates ◽  
Atomic Force ◽  
Carbon Structures

ABSTRACTVery hot carbon vapor was deposited on highly-oriented pyrolytic graphite (HOPG) and on sapphire substrates. Using atomic force microscopy, the obtained carbon structures are analyzed. It is found that carbon nanotubes and cones had formed on the graphite substrate but not on sapphire. Instead, spherical-type nanoparticles are analyzed on sapphire. A particle with double-conical shape is found on the graphite substrate. The two observed cone angles 19° and 60° are explained by perfect network closure of sectors of curled graphene sheets.

Fabrication and Characterization of Multiwalled Carbon Nanotubes-Alumina Hybrid Compound: Comparison of Various Supported Catalyst

2013 ◽  
Vol 594-595 ◽  
pp. 378-381
Author(s):  
Nosbi Norlin ◽  
Hazizan Md Akil
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Supported Catalysts ◽  
Chemical Vapour ◽  
Supported Catalyst ◽  
Multiwalled Carbon ◽  
Hybrid Compound ◽  
Carbon Structures ◽  
Catalyst Effect

Hybrid compounds of multiwalled carbon nanotubes-alumina (MWCNT-Al2O3) were grown by chemical vapour deposition (CVD) method of methane. The catalyst effect and growth of the synthesis of the multiwalled carbon nanotubes-alumina (MWCNT-Al2O3) hybrid compound in three different supported catalysts (Ni, Co and Fe nitrates) were being compared. X-Ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM) were employed for the characterization of the hybrid compound. The results revealed that the Ni nitrates catalysts showed a better growth rate performance than Co Nitrates and Fe Nitrates. With respect to the diameter of the MWCNT-Al2O3,the Fe nitrate showed lengthens in diameter compared to Co Nitrates and Ni Nitrates catalyst. This indicated that the growths of these carbon structures can be controlled and manipulated by the supported catalyst.

scholarly journals Applications and Nanotoxicity of Carbon Nanotubes and Graphene in Biomedicine

2012 ◽  
Vol 2012 ◽  
pp. 1-19 ◽  
Author(s):  
Caitlin Fisher ◽  
Amanda E. Rider ◽  
Zhao Jun Han ◽  
Shailesh Kumar ◽  
Igor Levchenko ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanostructures ◽  
Biomedical Applications ◽  
Scientific Community ◽  
Research Progress ◽  
Great Promise ◽  
Carbon Structures ◽  
Safety And Toxicity ◽  
Therapeutic Tools ◽  
Biomedical Fields

Owing to their unique mechanical, electrical, optical, and thermal properties, carbon nanostructures including carbon nanotubes and graphenes show great promise for advancing the fields of biology and medicine. Many reports have demonstrated the promise of these carbon nanostructures and their hybrid structures (composites with polymers, ceramics, and metal nanoparticles, etc.) for a variety of biomedical areas ranging from biosensing, drug delivery, and diagnostics, to cancer treatment, tissue engineering, and bioterrorism prevention. However, the issue of the safety and toxicity of these carbon nanostructures, which is vital to their use as diagnostic and therapeutic tools in biomedical fields, has not been completely resolved. This paper aims to provide a summary of the features of carbon nanotube and graphene-based materials and current research progress in biomedical applications. We also highlight the current opinions within the scientific community on the toxicity and safety of these carbon structures.

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