11 documents found, page 1 of 2

A simple protocol for the synthesis of perylene bisimides from perylene tetraca...

Perylene bisimides are highly attractive polycyclic aromatic hydrocarbons due to their photostability associated to unique and characteristic photochemical properties. They have been widely used for analytical purposes, despite the hydrophobicity of most of these compounds. The ring substitution pattern plays an important role in fine-tuning the physicochemical properties that govern solubility and aggregation....

Grafting of adipic anhydride to carbon nanotubes through a Diels-Alder cycloadd...

Different reactions have been reported for the successful functionalization of carbon nanotubes (CNT). The Diels-Alder cycloaddition is recognized as a plausible chemical approach, but few reports are known where this strategy has been used. In this study, the functionalization was performed by 1,3-butadiene generated from 3-sulfolene under heating conditions in diglyme. This simple and easily scalable method r...

Comportamento voltamétrico de perilenos bismides modificados em GCE e SPE

Uma das necessidades mais emergentes no planeta é a deteção e quantificação de diversos analitos prejudiciais aos seres vivos, presentes no meio ambiente, de uma forma rápida, com baixo custo e com elevada seletividade. Os screen printed electrodes (SPE) têm sido usados extensivamente como transdutores de sensores químicos para vários analitos importantes. A modificação da superfície dos SPEs com moléculas capa...

Non-covalent modification of voltammetric SPE sensors

Screen printed electrodes (SPE) are highly attractive as transducers of chemical sensors for the screening of a number of important analytes. The surface modification of these electrodes is easily carried out in order to achieve higher sensitivity. Carbon nanostructures have been extensively used for this purpose, as the number of active sites can be greatly increased. On the other hand, the immobilization of a...

Simple strategies for stable aqueous suspensions of carbon nanotubes

Carbon nanotubes (CNT) are attractive nanoparticles for biological applications due to their broad absorption of light in the UV-Vis-NIR, NIR photoluminescence, unique Raman signature, photothermal response, and large surface area for the covalent and non-covalent conjugation of contrast agents and drugs, DNA/RNA. However, pristine CNT are highly hydrophobic and not biocompatible, requiring functionalization wi...

The solvent effect on the sidewall functionalization of multi-walled carbon nan...

The Diels-Alder cycloaddition of maleic anhydride to multi-walled carbon nanotubes (MWCNT) was performed in dimethyl sulfoxide (DMSO) (190°C, 24 h) and in 2-chorotoluene (150°C, 48 h). The functionalized MWCNT were characterized by thermogravimetry, elemental analysis, X-ray photoelectron spectroscopy, and potentiometric titration allowing a clear perception of the solvent involvement on the functionalization r...

Efficient dispersion of multi-walled carbon nanotubes in aqueous solution by no...

A selection of bolaamphiphilic perylene bisimides (PBI) were prepared from the reaction of perylenetetracarboxylic dianhydride with a-amino acids. These molecules were obtained in good yield using a simple synthetic protocol and avoiding the need for complex purification methods, a major advantage for future applications. Carbon nanotubes (CNT) were dispersed in an aqueous solution of the PBI, buffered at pH 7,...

Polymer composites with graphene nanoribbons formed by the unzipping of carbon ...

Functionalization of CNTS with maleic anhydride

The outstanding properties of carbon nanotubes (CNTs) [1] are mainly related with their unique structural features. However, the high π-π staking between the tubes is a major drawback for their manipulation and interaction with other materials. Chemical functionalization has been used as a convenient tool to improve their performance in various applications [2]. The work reports the functionalization of multi-w...

Formation of graphene nanoribbons in solution

Recently, the formation of graphene by exfoliation of carbon nanotubes (CNT) has shown increasing interest. This process originates graphene nanoribbons (GNR) that are expected to present excellent electrical properties, depending on their width and on their edge shape [1]. Several methods for the unzipping of graphene from CNT were proposed along the past few years [2-6]. These methods often present some limit...