Polycondensation of Hexamethylenetetramine in Anhydrous Acid Media as a New Approach to Carbyne-Like Materials and Its Application as Dispersant of Carbon Materials

Aminocumulene (AC), a technical name that results from the hexamethylenetetramine polycondensation in anhydrous sulfuric acid, was successfully performed toward the synthesis of oligomeric cumulenic compounds made up of carbyne-like (=C=C)x fragments as a main moiety together with amino endcapping groups. The tentative mechanism for the synthesis of the soluble and insoluble AC likely included the participation of carbene species as an intermediate. Spectral properties obtained from UV-Vis, infrared, and Raman spectroscopies, and surface chemistry analysis through X-ray photoelectron spectroscopy of the soluble AC confirmed the presence of a mixture of linear and branched aminocumulene-based oligomers. AC displayed high performance as a dispersant and stabilizer agent of both multi-walled carbon nanotubes and graphene in aqueous solutions after powerful insonation treatment under controlled temperature compared to the most commonly used dispersant agents. Thereby, AC is vitally important for the preparation of carbonaceous materials based on nanoinks in a wide variety of fields.

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Synthesis and Characteristics of Hierarchical Nanostructure Fe3O4 Coated Multi-Walled Carbon Nanotubes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.926-930.258 ◽

2014 ◽

Vol 926-930 ◽

pp. 258-261

Author(s):

Jing Heng Deng ◽

Kan Ping Yu ◽

Jian Guo Xie

Keyword(s):

Electron Microscopy ◽

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Solvothermal Process ◽

X Ray ◽

Hierarchical Nanostructure ◽

Transmission Electron ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Scanning Electron

Hierarchical nanostructure Fe3O4/multi-walled carbon nanotubes (Fe3O4/MWCNTs) were prepared by solvothermal process using acid treated MWCNTs and iron acetylacetonate in ethylene glycol as reduction reagent. The materials were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET). The results showed that petal-like hierarchical Fe3O4 grew on MWCNTs and the Fe3O4 nanoparticles had diameters in the range of 55-110 nm. It was a facile approach to grow hierarchical nanoFe3O4.

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Combining Carbon Nanotubes and Chitosan for the Vectorization of Methotrexate to Lung Cancer Cells

Materials ◽

10.3390/ma12182889 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2889 ◽

Cited By ~ 9

Author(s):

Giuseppe Cirillo ◽

Orazio Vittorio ◽

David Kunhardt ◽

Emanuele Valli ◽

Florida Voli ◽

...

Keyword(s):

Lung Cancer ◽

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Ph Responsive ◽

Carbon Nanostructure ◽

X Ray ◽

Transmission Electron ◽

Multi Walled Carbon Nanotubes ◽

Responsive Behavior ◽

Walled Carbon Nanotubes

A hybrid system composed of multi-walled carbon nanotubes coated with chitosan was proposed as a pH-responsive carrier for the vectorization of methotrexate to lung cancer. The effective coating of the carbon nanostructure by chitosan, quantified (20% by weight) by thermogravimetric analysis, was assessed by combined scanning and transmission electron microscopy, and X-ray photoelectron spectroscopy (N1s signal), respectively. Furthermore, Raman spectroscopy was used to characterize the interaction between polysaccharide and carbon counterparts. Methotrexate was physically loaded onto the nanohybrid and the release profiles showed a pH-responsive behavior with higher and faster release in acidic (pH 5.0) vs. neutral (pH 7.4) environments. Empty nanoparticles were found to be highly biocompatible in either healthy (MRC-5) or cancerous (H1299) cells, with the nanocarrier being effective in reducing the drug toxicity on MRC-5 while enhancing the anticancer activity on H1299.

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Surface characterization of oxygen-functionalized multi-walled carbon nanotubes by high-resolution X-ray photoelectron spectroscopy and temperature-programmed desorption

Applied Surface Science ◽

10.1016/j.apsusc.2007.07.120 ◽

2007 ◽

Vol 254 (1) ◽

pp. 247-250 ◽

Cited By ~ 151

Author(s):

Wei Xia ◽

Yuemin Wang ◽

Ralf Bergsträßer ◽

Shankhamala Kundu ◽

Martin Muhler

Keyword(s):

Carbon Nanotubes ◽

High Resolution ◽

Photoelectron Spectroscopy ◽

Surface Characterization ◽

Temperature Programmed Desorption ◽

X Ray ◽

Multi Walled Carbon Nanotubes ◽

Temperature Programmed ◽

Walled Carbon Nanotubes

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Deposition of Titania Nanoparticles on the Surface of Acid Treated Multiwalled Carbon Nanotubes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.117.27 ◽

2010 ◽

Vol 117 ◽

pp. 27-32

Author(s):

Sabita Shrestha ◽

Chong Yun Park

Keyword(s):

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Decomposition Temperature ◽

Titania Nanoparticles ◽

Multiwalled Carbon ◽

Chemical Route ◽

X Ray ◽

Transmission Electron ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Titanium dioxide (Titania, TiO2) nanoparticles have been deposited on the surface of acid treated multi-walled carbon nanotubes (MWCNTs) by simple chemical route. The resultant TiO2/MWCNTs composites were characterized by different techniques. The oxidation of MWCNTs and presence of titania nanoparticles on the surface of MWCNTs is confirmed by transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. TEM image shows the size of titania nanoparticles are around 5 nm. Raman spectroscopy showed the oxidation and functionalization of nanotubes. The TGA curve showed decrease in thermal decomposition temperature of MWCNTs after oxidation and attachment with titania nanoparticles.

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Catalytic activity of CuxMnxFe3-2xO4/multi-walled carbon nanotubes (0 ≤ x ≤ 0.1) nanocomposites for p-nitrophenol degradation in catalyst/H2O2 system

Water Science & Technology ◽

10.2166/wst.2019.236 ◽

2019 ◽

Vol 79 (12) ◽

pp. 2345-2356

Author(s):

Jiye Yu ◽

Xiaojun Tian ◽

Mingwang Liu ◽

Zhenzhen Jia ◽

Hongqin Fang ◽

...

Keyword(s):

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Cod Removal ◽

Precipitation Method ◽

Heterogeneous Fenton ◽

Removal Rates ◽

X Ray ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Mn Doped

Abstract Heterogeneous Fenton oxidation has become a very important wastewater-treatment method and its catalyst is crucial for good treatment effect. In order to improve the catalytic properties, the Cu and Mn elements were doped for CuxMnxFe3-2xO4/multi-walled carbon nanotubes (CuxMnxFe3-2xO4/MWCNTs) nanocomposites (0 ≤ x ≤ 0.1) by co-precipitation method. The structure, morphology and surface properties of the nanocomposites were characterized by X-ray powder diffractometer (XRD), N2-physisorption analysis, transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS). The CuxMnxFe3-2xO4/MWCNTs nanocomposites were used as heterogeneous Fenton catalysts for p-nitrophenol (p-NP) degradation. The catalytic performances of the Cu and/or Mn doped nanocomposites have remarkable improvement compared with Fe3O4/MWCNTs nanocomposite, especially for both Cu and Mn doped catalyst. For CuxMnxFe3-2xO4/MWCNTs nanocomposites, the catalytic performance increases with increasing x value and reaches a maximum at 0.075 of x value. At optimal condition, the p-NP conversion rate reaches 96.4% in 10 min for Cu0.075Mn0.075Fe2.85O4/MWCNTs nanocomposite. However, the mentioned rate for Fe3O4/MWCNTs catalyst is only 14.5%. The chemical oxygen demand (COD) removal rates in 120 min for Cu0.075Mn0.075Fe2.85O4/MWCNTs and Fe3O4/MWCNTs catalysts are 82.7% and 67.3%, respectively. Furthermore, the p-NP conversion and COD removal rates of Cu0.075Mn0.075Fe2.85O4/MWCNTs nanocomposite still keep at 94.4% and 70.3% after five-time reuse, respectively. This catalyst shows good reusability for p-NP degradation and is very easy to recover from the treated water.

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Chemical Modification of Carbon Materials with Sulfur Functionalities

MRS Proceedings ◽

10.1557/proc-1039-p07-01 ◽

2007 ◽

Vol 1039 ◽

Author(s):

Takako Nakamura ◽

Tsuguyori Ohana

Keyword(s):

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Self Assembly ◽

Carbon Materials ◽

Irradiation Time ◽

Diamond Films ◽

Single Walled Carbon Nanotubes ◽

Assembly Process ◽

X Ray ◽

Walled Carbon Nanotubes

AbstractPhotolysis of cyclic disulfides in the presence of carbon materials such as diamond films and single-walled carbon nanotubes led to a surface modification to introduce thioalkylthiol functional groups, confirming by means of Raman, X-ray photoelectron spectroscopy and mass spectrometer measurements. The results on the value of S/C ratio of sulfur-modified diamond films depends on irradiation time by monitoring with XPS. Through thioalkylthiol moieties, an attachment of gold nanoparticles using self-assembly process was performed on carbon materials surfaces.

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Role of chemical funcionalization of carbon nanoparticles in epoxy matrices

Journal of Composite Materials ◽

10.1177/0021998317709082 ◽

2017 ◽

Vol 52 (4) ◽

pp. 449-464 ◽

Cited By ~ 6

Author(s):

Roger H Bello ◽

Luiz AF Coelho ◽

Daniela Becker

Keyword(s):

Carbon Nanotubes ◽

Photoelectron Spectroscopy ◽

Modulus Of Elasticity ◽

Graphene Nanoplatelets ◽

Neat Resin ◽

X Ray ◽

Transmission Electron ◽

The Matrix ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

The effects of the silanization of multi-walled carbon nanotubes and graphene nanoplatelets with 3-APTES on thermal, mechanical and electrical properties of epoxy nanocomposites were investigated. Nanocomposites containing pristine, oxidized and silanized nanoparticles of multi-walled carbon nanotubes or graphene nanoplatelets at two different concentrations (0.15 and 0.50 vol.%) were prepared by in situ polymerization without using solvents. The functionalized nanoparticles were characterized by Fourier-transform infrared, X-ray photoelectron spectroscopy, Raman spectroscopy and transmission electron microscope techniques. The oxidation and the silanization on the surface of both nanoparticles were confirmed by Fourier-transform infrared, X-ray photoelectron spectroscopy, Raman and transmission electron microscope analysis. The thermal properties of all studied materials were analyzed by differential scanning calorimetry and the mechanical properties by nanoindentation. The addition of both nanoparticles (pristine and functionalized) into the matrix did not show significant variations on thermal properties, but decreased values for glass transition temperature (Tg) compared to the neat resin. Higher values for modulus of elasticity and hardness of epoxy/nanocomposites were obtained when silanized multi-walled carbon nanotubes or oxidized graphene nanoplatelets were added into the matrix. Adding 0.15 vol.% of silanized multi-walled carbon nanotubes the modulus of elasticity increased in approximately 60%, whereas 0.50 vol.% this increase was greater than 90% compared to the neat resin. While adding 0.15 vol.% of oxidized graphene nanoplatelets, the modulus of elasticity increased approximately 83%, whereas 0.50 vol.% this increase was greater than 88% compared to the neat resin. The formation of percolating networks has been achieved only by pristine multi-walled carbon nanotubes addition at a concentration of 0.50 vol.% and by silanized graphene nanoplatelets at a concentration of 0.15 vol.%. However, for both carbon-based nanoparticles conductivities on the order of 10−7 S/m for frequencies near 100 Hz were observed.

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