Noncovalent functionalization of graphene with a Ni(II) tetraaza[14]annulene complex.

The few-layer graphene, produced by exfoliation of graphite in 4-methylanisole, was noncovalently functionalized with the Ni(ii) complex of 5,7,12,14-tetramethyldibenzo-1,4,8,11-tetraazacyclotetradeca-3,5,7,10,12,14-hexaene (Ni(ii)-tetramethyldibenzotetraaza[14]annulene, or NiTMTAA), which is a simple model of more complex porphyrins and phthalocyanines. The resulting hybrid materials with different content of NiTMTAA were characterized by means of thermogravimetric analysis, scanning and transmission electron microscopy (SEM and TEM, respectively), atomic force microscopy (AFM), energy dispersive X-ray, Fourier-transform infrared (FTIR), Raman and UV-visible spectroscopy, as well as fluorescence and conductivity measurements. Additional information on the mechanisms of NiTMTAA interaction with graphene was obtained from density functional theory (DFT) and molecular mechanics (MM) calculations.

"Green" functionalization of pristine multi-walled carbon nanotubes with long-chain aliphatic amines.

Short pristine multi-walled carbon nanotubes (MWNTs) were functionalized with a series of long-chain (including polymeric) aliphatic amines, namely octadecylamine (ODA), 1,8-diaminooctane (DO), polyethylene glycol diamine (PEGDA) and polyethylenimine (PEI), via two "green" approaches: (1) gas-phase functionalization (for volatile ODA and DO) and (2) direct heating in the melt (for polymeric PEGDA and PEI). Both of them consist in one-step reaction between MWNTs and amine without the use of organic solvents. The nanostructures obtained were characterized by using infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy.

Microwave irradiation of pristine multi-walled carbon nanotubes in vacuum.

The goal of the present paper was to study the behavior of commercially available pristine multi-walled carbon nanotubes (MWNTs) under microwave irradiation (exposures up to 200 s) in vacuum, by means of several experimental techniques. An intense glow and heating of the nanotube samples were observed. Raman spectra, scanning electron microscopy (SEM) and scanning tunneling microscopy (STM) images of the processed nanotubes did not show considerable changes as compared to those for pristine MWNTs.

Nanohybrids of nylon 6 with multi-walled carbon nanotubes: solvent-free polymerization of epsilon-caprolactam under variable experimental conditions.

The solvent-free polymerization of epsilon-caprolactam on 1,8-diaminooctane-functionalized multi-walled carbon nanotubes (DA-MWNTs) is proposed as a simple and ecologically friendly approach to the preparation of carbon nanotubes/nylon 6 hybrid materials. The main goal of the present study was to find a minimum temperature resulting in an efficient epsilon-caprolactam polymerization, along with the optimization of the weight ratio of DA-MWNTs to epsilon-caprolactam and reaction time. The effect of temperature was studied in the range of 170 degrees C to 210 degrees C.

Fullerene C60 films cross-linked with octane-1,8-dithiol: preparation, characterization and the use as template for chemical deposition of gold nanoparticles.

We report on the preparation of fullerene C60 thin films chemically cross-linked with octane-1,8-dithiol, which are capable of binding gold nanoparticles. The formation of a polymer was directly proved by means of laser desorption/ionization time-of-flight mass spectra, in which we observed the cleavage of fullerene-dithiol polymer at different bonds. Fourier-transform infrared, Raman and UV-visible spectra of the functionalized films exhibited notorious changes due to the formation of new covalent bonds between C60 molecules and bifunctional thiol.

Noncovalent functionalization of carbon nanotubes with porphyrins: meso-tetraphenylporphine and its transition metal complexes.

Noncovalent functionalization of carbon nanotubes with meso-tetraphenylporphine (H2TPP) and its metal(II) complexes NiTPP and CoTPP was studied by means of different experimental techniques and theoretical calculations. As follows from the experimental adsorption curves, free H2TPP ligand exhibits the strongest adsorption of three porphyrins tested, followed by CoTPP and NiTPP. At the highest porphyrin concentrations studied, the adsorption at multi-walled carbon nanotubes was about 2% (by weight) for H2TPP, 1% for CoTPP, and 0.

Deposition of gold nanoparticles onto thiol-functionalized multiwalled carbon nanotubes.

Gold nanoparticles were deposited on the surface of multiwalled carbon nanotubes (MWNTs) functionalized with aliphatic bifunctional thiols (1,4-butanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol, and 2-aminoethanethiol) through a direct solvent-free procedure. Small gold particles, with a narrow particle size distribution around 1.7 nm, were obtained on 1,6-hexanedithiol-functionalized MWNTs.