Multi-walled carbon nanotubes

Part 2 book "Electrical conduction in graphene and nanotubes" includes content: Superconductivity, metallic (or superconducting) swnts, magnetic susceptibility, magnetic oscillations, quantum hall effect, quantum hall effect in graphene, seebeck coefficient in multiwalled carbon nanotubes, miscellaneous.

186p dianmotminh01 17-05-2024 4 2   Download

In this work, a functional nanocomposite consisting of silver nanoparticles and multiwalled carbon nanotubes (MWCNTs-Ag) was successfully synthesized using a two-step chemical process. The MWCNTsAg nanocomposite has been studied as a surface-enhanced Raman scattering (SERS) sensing platform for detection of methylene blue (MB) dye in an aqueous medium.

6p viberbers 09-08-2023 6 4   Download

Transparent and conductive thin films of multiwalled carbon nanotubes (MWCNTs) with different lengths were prepared on glass substrates by the spin coating method. In order to reduce the MWCNTs length, they were functionalized.

6p viberbers 09-08-2023 6 3   Download

A simple approach to constructing a double-layer voltammetric sensor is described. The poly(malachite green) (PMG) and multiwalled carbon nanotubes (MWCNTs) were coimmobilized at the surface of the glassy carbon electrode (GCE) for fabrication of PMG/MWCNT/GCE. The modified electrode was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV), and chronoamperometric techniques.

15p langthannam 29-12-2021 9 0   Download

The electrochemical oxidation of 2,6-diaminopurine (2,6-DAP) was studied in pH 7.4 phosphate buffer solution on multiwall carbon nanotube modified glassy carbon electrode (MWCNT/GCE) over a temperature range of 20 to 50 ◦ C using cyclic voltammetry. 2,6-DAP oxidation on MWCNT/GCE showed a well-defined and irreversible oxidation peak at about 0.72 V vs. Ag/AgCl at pH 7.4. The oxidation potential of 2,6-DAP linearly varied with pH over the range of 3.0 to 10.0 with a slope of –0.0547 V/pH, implying that 2 protons were accompanied by 2 electrons transferred in the electrochemical reaction.

10p langthannam 29-12-2021 10 0   Download

Thiolated chitosan (CS–TGA) was prepared using chitosan (CS) and thioglycolic acid (TGA). Then MWCNTs were added to the mixture of CS–TGA and CS to prepare the CS/CS–TGA/MWCNs porous composite by freeze-drying method and this composite was used to modify an indium tin oxide glass electrode. The electrode was used as a sensor for Pb2+. The morphology and structure of the composite were characterized by infrared spectroscopy and scanning electron microscope, and their electrochemical behavior was also studied.

7p langthannam 29-12-2021 13 1   Download

The power density of direct methanol fuel cells (DMFCs) can be changed by using different anode materials. Especially porous materials are preferred for the anode. In the present study, multiwall carbon nanotubes were first injected into graphite. Then, by depositing nickel, a catalyst was prepared for use as the anode material of the DMFC. This catalyst was named Ni@MWNTs. The oxidation of methanol and some kinetic parameters were investigated in KOH solution.

11p langthannam 29-12-2021 8 0   Download

The use of multiwalled carbon nanotubes (CNTs) in sol-gel synthesized titanium dioxide (TiO2) photocatalysts as templates was systematically studied. CNTs have high oxidative thermal stability and the controlled removal of CNTs can be achieved at lower temperatures under air flow by the use of Na, Fe, and Co as a catalyst. These catalysts helped to reduce the oxidation temperature of CNTs; thus anatase phase was achieved without significant sintering.

15p langthannam 29-12-2021 8 0   Download

In this work, the electrochemical oxidation of deferasirox at a multiwall carbon nanotube paste electrode (MWCNTPE) was described. The electrochemical behavior of deferasirox was studied using cyclic voltammetry and chronoamperometry techniques and parameters such as charge transfer coefficient (α), the number of electrons involved in the rate-determining step (na), and diffusion coefficient (D) were calculated.

12p tudichquannguyet 29-11-2021 10 2   Download

Enhanced electrocatalytic reduction of oxygen is achieved using Pt nanoparticle-modified copper phthalocyanine-multiwalled carbon nanotube (PtNPs/CuPc-CNT) composite film on a glassy carbon electrode (PtNPs/CuPcCNT/GCE). The PtNPs/CuPc-CNT/GCE surface is characterized by scanning electron microscopy, transmission electron microscopy, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The electrocatalytic activity of composite electrodes in the oxygen reduction reaction is investigated by cyclic voltammetry and rotating-disk electrode measurements.

16p tudichquannguyet 29-11-2021 7 1   Download

Phenmedipham is an herbicide used especially in the sugar beet harvest to fight against broad-leaved weeds and studies of its voltammetric behavior and detection have not been done before. The superior properties of carbon nanotubes such as electrical conductivity, mechanical strength, and wide potential ranges make them attractive for chemical sensors and the phenmedipham compound gave an oxidation peak at +1320 mV (vs. Ag/AgCl) on the nanostructured multiwalled carbon nanotube paste electrode.

11p tudichquannguyet 29-11-2021 7 1   Download

A new sensitive and accurate solid-phase extraction method for preconcentration of trace amounts of cadmium and lead in various environmental samples prior to flame atomic absorption spectrometry determination has been developed. The proposed method is based on the utilization of multiwalled carbon nanotubes in combination with 5-benzyl-4-[-chlororbenzylidene amine]-4H-1,2,4-triazole-3-thiol (BCBATT) as a solid-phase sorbent with the aid of ultrasonication. The effect of the preconcentration parameters was investigated.

14p tudichquannguyet 29-11-2021 5 1   Download

This work reports an electrochemical sensor with a modified glassy carbon electrode for the detection of kaempferol. The method was tailored by the immobilization of multiwalled carbon nanotubes (MWCNTs) assimilated with Fe2O3 nanoparticles (NPs) onto the electrode surface to detect kaempferol using differential pulse voltammetry. Thermogravimetric, transmission electron microscopic, cyclic, and differential voltammetric techniques were employed to characterize the developed electrochemical sensor. The kaempferol produces an anodic quasireversible peak at pH 6.

15p tudichquannguyet 29-11-2021 8 1   Download

Glucose oxidase was covalently immobilized to a porous electrode, which was developed by using ferrocene functionalized polyethyleneimine, multiwall carbon nanotubes, and carbon cloth for biofuel cell applications in our recent studies. The kinetics parameters (i.e. kM, Vmax) and other parameters required for the modeling study were determined experimentally. Fuel cell flow channel geometry was analyzed by a computational fluid dynamics modeling approach. Substrate flow rate and mass transfer for each proposed channel type were considered in the simulations.

17p tudichquannguyet 29-11-2021 5 1   Download

Bioanode stability with glucose oxidase was enhanced significantly by covalent crosslinking without substantial enzymatic activity and affinity loss. Initially, glucose oxidase was immobilized by aldehyde groups on the electrode that was developed using ferrocenecarboxaldehyde, polyethyleneimine, multiwall carbon nanotubes, and carbon cloth for biofuel cell applications. The glucose oxidase half-life was extended by more than 4 times, from 27.2 to 124.7 h, after the electrode was crosslinked.

10p tudichquannguyet 29-11-2021 6 2   Download

In this study, microwave-assisted ammonia decomposition reaction was investigated over molybdenum incorporated catalysts. Due to the selective, volumetric, and noncontact heating properties of the microwave system, higher conversion values could be achieved at relatively lower reaction temperatures, which is important for on-site COx-free hydrogen production. Multiwall carbon nanotube-supported molybdenum catalysts were prepared following the impregnation procedure with different metal loading (3.5%–12.

16p tudichquannguyet 29-11-2021 11 0   Download

This study deals with selective separation of mono- and divalent cations from aqueous salt solutions using polymeric films based on polyethylene (PE) and polyamide6 (PA6), and two different commercial nanofiltration (NF) membranes. The diffusion rates (D) of ions (Na+ and Ca2+), separation factors (α) and ion rejections (R) of the films and NF membranes are examined comparatively as well as their surface morphology and hydrophilicity. It is observed that the diffusion rates of Na + are in the range of 0.7–1.8 × 10 −8cm2.

14p tudichquannguyet 29-11-2021 8 2   Download

This study is the development of a new solid phase extraction method based on using magnetic multiwalled carbon nanotubes impregnated with 1-(2-pyridylazo)2-naphthol (PAN) for separation, preconcentration, and flame atomic absorption spectrometric determination of Pb(II) and Cu(II). Optimization of the method was done by investigating pH effect, amount of magnetic multiwalled carbon nanotubes impregnated with PAN, eluent type and volume, matrix effects, and volume of the sample. The optimum adsorbent amount was found to be 75 mg and the optimum pH value was found as 5.5.

9p tudichquannguyet 29-11-2021 7 1   Download

This study reports a detailed analysis of an electrode material containing poly(phenolphthalein), carbon nanotubes and gold nanoparticles which shows superior catalytic effect towards to hydrazine oxidation in Britton–Robinson buffer (pH 10.0). Glassy carbon electrode was modified by electropolymerization of phenolphthalein (PP) monomer (poly(PP)/GCE) and the multiwalled carbon nanotubes (MWCNTs) was dropped on the surface. This modified surface was electrodeposited with gold nanoparticles (AuNPs/CNT/poly(PP)/GCE).

21p tudichquannguyet 29-11-2021 10 0   Download

Herein, an adsorptive stripping linear sweep voltammetric technique was described to determine spiramycin, a macrolide antibiotic, using a carboxylic multiwalled glassy carbon electrode modified with carbon nanotubes. The main principle of the analytical methodology proposed was based on the preconcentration of spiramycin by open-circuit accumulation of the macrolide onto the modified electrode surface. As a result of the adsorption affinity of spiramycin to the modified surface, the sensitivity of the glassy carbon electrode was significantly increased for the determination of spiramycin.

12p tudichquannguyet 29-11-2021 6 1   Download