Palladium NPs supported on novel imino-pyridine-functionalized MWCNTs: efficient and highly reusable catalysts for the Suzuki–Miyaura and Sonogashira coupling reactions

2016 ◽  
Vol 40 (6) ◽  
pp. 4945-4951 ◽  
Author(s):  
Mehdi Adib ◽  
Rahman Karimi-Nami ◽  
Hojat Veisi
Keyword(s):  
Carbon Nanotubes ◽  
Coupling Reactions ◽  
Sonogashira Coupling ◽  
Heterogeneous Nanocatalyst ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

In this article a new heterogeneous nanocatalyst based on palladium supported on functionalized multi-walled carbon nanotubes (MWCNTs) has been introduced.

scholarly journals Multifunctional Ionogels Incorporated with Lanthanide (Eu3+, Tb3+) Complexes Covalently Modified Multi-Walled Carbon Nanotubes

Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1099 ◽  
Author(s):  
Qiuping Li
Keyword(s):  
Carbon Nanotubes ◽  
Ionic Liquids ◽  
Uv Light ◽  
Green Emission ◽  
Sem Images ◽  
Hybrid Gels ◽  
Multi Walled Carbon Nanotubes ◽  
Electric Materials ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

Ionogels refer to an emerging composite material made from the confinement of ionic liquids within some specific cross-linked network matrices. They have potential applications in areas such as electrochemical and optical-electric materials. Incorporation of lanthanide (Eu3+, Tb3+) complexes covalently functionalized multi-walled carbon nanotubes (MWCNTs) in ionogels provide new ideas to design and synthesize novel luminescent hybrid materials that have excellent characteristics of luminescence and ionic conductivity. Here, the multifunctional ionogels were synthesized by confining an ionic liquid and the rare earth functionalized MWCNTs in the cross-linked polymethyl methacrylate (PMMA) networks, resulting in a novel optical/electric multifunctional hybrid material. The SEM images and digital photographs suggest that the lanthanide functionalized MWCNTs are evenly dispersed in the hybrid matrices, thus leading to a certain transparency bulky gel. The resulting ionogels exhibit certain viscosity and flexibility, and display an intense red/green emission under UV-light irradiation. The intrinsic conductibility of the embedded ionic liquids and carbon nanotubes in conjunction with the outstanding photoluminescent properties of lanthanide complexes makes the soft hybrid gels a material with great potential and valuable application in the field of optical-electric materials.

A novel strategy for the synthesis of sulfur-doped carbon nanotubes as a highly efficient Pt catalyst support toward the methanol oxidation reaction

2017 ◽  
Vol 5 (36) ◽  
pp. 19467-19475 ◽  
Author(s):  
Jing-Jing Fan ◽  
You-Jun Fan ◽  
Rui-Xiang Wang ◽  
Sheng Xiang ◽  
Hua-Guo Tang ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Oxidation Reaction ◽  
Catalyst Support ◽  
Pt Nanoparticles ◽  
Pt Catalyst ◽  
Methanol Oxidation Reaction ◽  
Multi Walled Carbon Nanotubes ◽  
Novel Strategy ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

Sulfur-doped multi-walled carbon nanotubes (S-MWCNTs) derived from PEDOT-functionalized MWCNTs can significantly improve the dispersion of supported Pt nanoparticles and enhance their electrocatalytic performance for the MOR.

scholarly journals Application of Functionalized Multi-Walled Carbon Nanotubes for Growth Enhancement of Mustard Seed Germination

2019 ◽  
Vol 20 (1) ◽  
pp. 120
Author(s):  
Agus Subagio ◽  
Erma Prihastanti ◽  
Ngadiwiyana Ngadiwiyana
Keyword(s):  
Carbon Nanotubes ◽  
Mustard Seed ◽  
Growth Enhancement ◽  
Beneficial Effects ◽  
Carboxylic Groups ◽  
Multi Walled Carbon Nanotubes ◽  
Inner Diameter ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts ◽  
Mustard Seeds

Multi-walled carbon nanotubes (MWCNTs) are one of the nanomaterials that can be applied to agriculture. This work investigates the beneficial effects of MWCNT function on mustard plants. In this study, the material of MWCNTs is functionalized with nitric acid to attach the carboxylic group onto the tube wall. The functionalized MWCNTs were characterized by SEM, TEM, XRD, and FTIR. The MWCNT diameter produced ranges from 20 to 50 nm and the inner diameter is 5 to 10 nm at the pyrolysis temperature of 900 °C. It was found that crystallites of the MWCNTs have (002) and (100) directions. There is a weak peak in MWCNTs prior to the functionalization process due to the presence of metal carbide (Fe3C), which serves as an active catalyst. FTIR results clearly indicate the presence of hydroxyl and carboxylic groups. These functionalized MWCNTs were dispersed into distilled water with various concentrations at 25, 50 and 75 µg/mL. By utilizing an immersion time of 24 h, mustard (Brassica juncea) seeds were soaked in each functionalized and non-functionalized MWCNT solution. Functionalized MWCNT solution at a concentration of 50 µg/mL was found to affect the growth of mustard seeds more significantly.

scholarly journals Covalent Immobilization of Tyrosinase onto Multi-walled Carbon Nanotubes and Its Potential Use In Phenol Biosensing

2014 ◽  
Vol 7 (1) ◽  
Author(s):  
Shafinaz Shahir ◽  
Boon Kai Tai ◽  
Zaiton Abdul Majid ◽  
Nor Aziah Buang
Keyword(s):  
Carbon Nanotubes ◽  
Covalent Immobilization ◽  
Limiting Current ◽  
Reduction Peak ◽  
Covalently Bonded ◽  
Amide Carbonyl ◽  
Multi Walled Carbon Nanotubes ◽  
Surface Modified ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

The possibility of modifying the surface properties of multi-walled carbon nanotubes (MWCNTs) has stimulated increasing interest in their application as components in biosensors. In this sense, it is possible to employ surface modified MWCNTs as support to immobilize biomaterials such as enzymes. In this study the enzyme tyrosinase was immobilized onto functionalized MWCNTs (fMWCNTs) via covalent bonding and activity of immobilized tyrosinase was measured via electrochemical detection of phenol. MWCNTs were first treated with sulphuric acid and nitric acid with ratio 1 : 3 at 70ºC to introduce carboxylated groups (-COOH). The carboxyl moieties were then activated by treatment with a cross-linker, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) to enable tyrosinase immobilization via amide bonding. FTIR spectra of tyrosinase immobilized fMWCNTs showed the presence of peaks attributing to aliphatic C-N (1382 cm-1) and amide carbonyl (1639 cm-1) vibrations which confirmed successful covalent immobilization of tyrosinase onto fMWCNTs. Electrochemical measurements using tyrosinase-fMWCNTS-CPE revealed increasing limiting current values of reduction peak with increasing phenol concentrations at -200mV. The appearance of the reduction current indicates that the immobilization process retained the biological activity of the covalently bonded tyrosinase on fMWCNTs surface. This study has demonstrated the potential of using MWCNTs as support for enzyme immobilization and their application in biosensor technology.

CuCl heterogenized on metformine-modified multi walled carbon nanotubes as a recyclable nanocatalyst for Ullmann-type C–O and C–N coupling reactions

2018 ◽  
Vol 42 (4) ◽  
pp. 2782-2789 ◽  
Author(s):  
Elham Akhavan ◽  
Saba Hemmati ◽  
Malak Hekmati ◽  
Hojat Veisi
Keyword(s):  
Carbon Nanotubes ◽  
Synthesis Method ◽  
Coupling Reactions ◽  
Covalent Grafting ◽  
Multi Walled Carbon Nanotubes ◽  
Type C ◽  
Walled Carbon Nanotubes

Herein, a novel MWCNTs-Met/CuCl nanocatalyst synthesis method by metformine covalent grafting on the surface of carbon nanotubes and subsequent coordination with a CuCl catalyst is described.

Molecular Interactions in PA6, LCP and their Blend Incorporated with Functionalized Carbon Nanotubes

2010 ◽  
Vol 447-448 ◽  
pp. 634-638 ◽  
Author(s):  
Henry Kuo Feng Cheng ◽  
Nanda Gopal Sahoo ◽  
Lin Li ◽  
Siew Hwa Chan ◽  
Jian Hong Zhao
Keyword(s):  
Carbon Nanotubes ◽  
Polymer Matrices ◽  
Traditional Role ◽  
Factors Affecting ◽  
Crystal Polymer ◽  
Reinforcing Fillers ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts ◽  
Properties Of Composites

Multi-walled carbon nanotubes (MWCNTs) were functionalized with a carboxyl group (-COOH) to improve their dispersion in a nylon6 (PA6) matrix, a liquid crystal polymer (LCP) and their blend. This functionalized MWCNTs also achieved better interfacial adhesions with both polymer matrices and with both phases in the blend. The dispersion of MWCNT-COOH in the polymer matrices and their interfacial interactions with polymer molecules were found to be the most important factors affecting the properties of composites. Moreover, studies on morphological, rheological, and mechanical properties confirmed that a better miscibility between PA6 and LCP had been constituted in the presence of MWCNT-COOH. Therefore, it is observed that the functionalized MWCNTs not only played the traditional role as reinforcing fillers in the polymer matrices, but also performed a novel role as compatibilizers for their blend.

Thermo-mechanical properties of epoxy nanocomposites incorporating amino acid and acid functionalized multi-walled carbon nanotubes

2019 ◽  
Vol 54 (14) ◽  
pp. 1847-1861
Author(s):  
Alireza Bagherzade ◽  
Masoud Jamshidi
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Amino Acid ◽  
Epoxy Resin ◽  
Acid Treatment ◽  
Curing Temperature ◽  
Gravimetric Analysis ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
Functionalized Mwcnts

In this study, multi-walled carbon nanotubes (MWCNTs) were functionalized by both sulfuric/nitric acids and amino acids to form COOH and NH2/COOH/OH groups on their surface, respectively. The functionalized MWCNTs were characterized by Fourier Transform Infrared Spectroscopy, titration test, thermal gravimetric analysis, and solvent stability test. The results revealed that in each method, the functional groups were successfully attached to the surface of nanotubes. Acid treatment grafted more oxygen-containing groups compared to commercial carboxylated MWCNTs. The amino acid functionalized MWCNTs indicated improved stability in different solvents compared to raw and acid treated MWCNTs. These functionalized MWCNTs were incorporated into epoxy resin and the properties of the nanocomposites were evaluated by scanning electron microscopy, tensile test, dynamic mechanical thermal analysis, differential scanning calorimetry, and thermogravimetric analysis. The morphology of the nanocomposites revealed that acid and amino acid treated samples had better interaction with the epoxy resin. Compared to epoxy sample contained raw MWCNT (control) and commercial carboxylated MWCNTs, the addition of functionalized MWCNTs to the epoxy resin improved the tensile strength by 39% and 25% (for acid treated) and 46% and 33% (for amino acid treated), respectively. The best tensile properties for acid and amino acid treated samples were reached by MWCNTs acid treated at 110℃ for 15 min and MWCNTs treated in a 50 g/L aqueous solution of amino acid, respectively. Storage modulus of the epoxy samples which contained acid and amino acid treated MWCNTs were 1560 and 1900 MPa, respectively. The glass rubber transition temperature ( Tg) of the epoxy samples containing acid and amino acid treated nanotubes were increased by 1.1℃ and 5.9℃, respectively, compared to the control sample. Therefore, based on these mechanical properties, the epoxy samples containing nanotubes functionalized by amino acid exhibited the highest performance in the epoxy nanocomposite. Incorporating acid and amino acid treated MWCNTs accelerated the curing process of epoxy where the curing temperature decreased by 9.1℃ and 13.3℃, respectively. Because of the reaction between amine groups grafted on MWCNTs in the amino acid treatment and epoxide groups of the epoxy resin, this acceleration was more significant in the case of amino acid sample. Note that addition of functionalized MWCNTs to epoxy resin did not lead to increased thermal stability.

Sign in / Sign up

Export Citation Format

Share Document