Selective Oxidation of Cinnamyl Alcohol to Cinnamaldehyde over Functionalized Multi-Walled Carbon Nanotubes Supported Silver-Cobalt Nanoparticles

The selective oxidation of alcohols to aldehydes has attracted a lot of attention because of its potential use in agrochemicals, fragrances, and fine chemicals. However, due to homogenous catalysis, low yield, low selectivity, and hazardous oxidants, traditional approaches have lost their efficiency. The co-precipitation method was used to synthesize the silver-cobalt bimetallic catalyst supported on functionalized multi-walled carbon nanotubes (Ag-Co/S). Brunauer Emmet Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and X-ray diffraction (XRD) were used to characterize the catalyst. For the oxidation of cinnamyl alcohol (CA) with O2 as an oxidant, the catalyst’s selectivity and activity were investigated. The impacts of several parameters on catalyst’s selectivity and activity, such as time, temperature, solvents, catalyst dosage, and stirring speed, were comprehensively studied. The results revealed that in the presence of Ag-Co/S as a catalyst, O2 could be employed as an effective oxidant for the catalytic oxidation of cinnamyl alcohol to cinnamaldehyde (CD) with 99% selectivity and 90% conversion. In terms of cost effectiveness, catalytic activity, selectivity, and recyclability, Ag-Co/S outperforms the competition. As a result, under the green chemistry methodology, it can be utilized as an effective catalyst for the conversion of CA to CD.

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A novel co-precipitation method for preparation of Pt-CeO2 composites on multi-walled carbon nanotubes for direct methanol fuel cells

Journal of Power Sources ◽

10.1016/j.jpowsour.2009.12.115 ◽

2010 ◽

Vol 195 (12) ◽

pp. 3802-3805 ◽

Cited By ~ 50

Author(s):

Dao-Jun Guo ◽

Zhi-Hong Jing

Keyword(s):

Carbon Nanotubes ◽

Fuel Cells ◽

Direct Methanol Fuel Cells ◽

Precipitation Method ◽

Direct Methanol ◽

Multi Walled Carbon Nanotubes ◽

Methanol Fuel Cells ◽

Co Precipitation ◽

Walled Carbon Nanotubes

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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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Preparation and photocatalytic activity of multi-walled carbon nanotubes/Mg-doped ZnO nanohybrids

Materials Science-Poland ◽

10.1515/msp-2015-0083 ◽

2015 ◽

Vol 33 (3) ◽

pp. 460-469 ◽

Cited By ~ 5

Author(s):

C. S. Chen ◽

X. D. Xie ◽

S. Y. Cao ◽

T. G. Liu ◽

L. W. Lin ◽

...

Keyword(s):

Carbon Nanotubes ◽

Photocatalytic Activity ◽

Methyl Orange ◽

Precipitation Method ◽

Multi Walled Carbon Nanotubes ◽

Doped Zno ◽

Co Precipitation ◽

Walled Carbon Nanotubes ◽

Degradation Of Methyl Orange ◽

Mg Doped

Abstract Multi-walled carbon nanotubes/Mg-doped ZnO (MWNTs/Zn1-xMgxO) nanohybrids were prepared by co-precipitation method, and their photocatalytic activity for methyl orange (MO) was studied. Experimental results showed that Mg-doped ZnO nanoparticles were successfully deposited on the surface of MWNTs under annealing at 450 °C and 550 °C. The resultant MWNTs/Zn0.9Mg0.1O nanohybrids had better photocatalytic activity for degradation of methyl orange than pure ZnO: the rates of MO photodegradation were 100 % and 30 % for 1 h, respectively. The enhancement in the photocatalytic activity was attributed to the excellent electronic properties of MWNTs and Mg-doping.

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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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Measuring inside damage of individual multi-walled carbon nanotubes using scanning transmission X-ray microscopy

Applied Physics Letters ◽

10.1063/1.4883919 ◽

2014 ◽

Vol 104 (24) ◽

pp. 241602 ◽

Cited By ~ 2

Author(s):

Jinyin Liu ◽

Lili Bai ◽

Jian Wang ◽

Guanqi Zhao ◽

Xuhui Sun ◽

...

Keyword(s):

Carbon Nanotubes ◽

X Ray ◽

Scanning Transmission ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Effects of acid treatment duration and sulfuric acid molarity on purification of multi-walled carbon nanotubes

Open Physics ◽

10.2478/s11534-010-0017-9 ◽

2010 ◽

Vol 8 (6) ◽

Cited By ~ 1

Author(s):

Seyedeh Mortazavi ◽

Abdul Novinrooz ◽

Ali Reyhani ◽

Soghra Mirershadi

Keyword(s):

Carbon Nanotubes ◽

Sulfuric Acid ◽

Acid Solution ◽

Treatment Duration ◽

Acid Treatment ◽

Bimetallic Catalyst ◽

Chemical Vapor ◽

Destructive Effect ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

AbstractMulti-walled carbon nanotubes were synthesized using a Fe-Ni bimetallic catalyst supported by MgO using thermal chemical vapor deposition. Purification processes to remove unwanted carbon structures and other metallic impurities were carried out by boiling in sulfuric acid solution. Various analytical techniques such as TGA/DSC, Raman spectroscopy, SEM, HRTEM and EDAX were employed to investigate the morphology, graphitization and quality of the carbon nanotubes. The obtained results reveal the molarity of sulfuric acid and immersed time of the carbon nanotubes in the acid solution is very effective at purifying multi-walled carbon nanotubes. It was also found that 5 M concentration of boiling sulfuric acid for a 3 h treatment duration led to the highest removal of the impurities with the least destructive effect. Moreover, it was observed that acid treatment results in decreasing of CNTs’ diameter.

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Structure and Mechanical Properties of Multi-Walled Carbon Nanotubes-Filled Isotactic Polypropylene Composites Treated by Pressurization at Different Rates

Polymers ◽

10.3390/polym11081294 ◽

2019 ◽

Vol 11 (8) ◽

pp. 1294 ◽

Cited By ~ 1

Author(s):

Xiaoting Li ◽

Wenxia Jia ◽

Beibei Dong ◽

Huan Yuan ◽

Fengmei Su ◽

...

Keyword(s):

Carbon Nanotubes ◽

Isotactic Polypropylene ◽

Mechanical Tests ◽

High Yield ◽

Scanning Calorimetry ◽

X Ray ◽

Polypropylene Composites ◽

Pressurization Rate ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Isotactic polypropylene filled with 1 wt.% multi-walled carbon nanotubes (iPP/MWCNTs) were prepared, and their crystallization behavior induced by pressurizing to 2.0 GPa with adjustable rates from 2.5 to 1.3 × 104 MPa/s was studied. The obtained samples were characterized by combining wide angle X-ray diffraction, small angle X-ray scattering, differential scanning calorimetry, transmission electron microscopy and atomic force microscopy techniques. It was found that pressurization is a simple way to prepare iPP/MWCNTs composites in mesophase, γ-phase, or their blends. Two threshold pressurization rates marked as R1 and R2 were identified, while R1 corresponds to the onset of mesomorphic iPP formation. When the pressurization rate is lower than R1 only γ-phase generates, with its increasing mesophase begins to generate and coexist with γ-phase, and if it exceeds R2 only mesophase can generate. When iPP/MWCNTs crystallized in γ-phase, compared with the neat iPP, the existence of MWCNTs can promote the nucleation of γ-phase, leading to the formation of γ-crystal with thicker lamellae. If iPP/MWCNTs solidified in mesophase, MWCNTs can decrease the growth rate of the nodular structure, leading to the formation of mesophase with smaller nodular domains (about 9.4 nm). Mechanical tests reveal that, γ-iPP/MWCNTs composites prepared by slow pressurization display high Young’s modulus, high yield strength and high elongation at break, and meso-iPP/MWCNTs samples have excellent deformability because of the existence of nodular morphology. In this sense, the pressurization method is proved to be an efficient approach to regulate the crystalline structure and the properties of iPP/MWCNTs composites.

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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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