Search results for "Fuller"

Non-conventional methods and media for the activation and manipulation of carbon nanoforms

2013

Very often, chemical transformations require tedious and long procedures, which, sometimes, can be avoided using alternative methods and media. New protocols, enabling us to save time and solvents, allow us also to explore new reaction profiles. This Tutorial Review focuses on the physical and chemical behavior of carbon nanoforms, CNFs (fullerenes, nanotubes, nanohorns, graphene, etc.) when non-conventional methods and techniques, such as microwave irradiation, mechano-chemistry or highly ionizing radiations are employed. In addition, the reactivity of CNFs in non-conventional media such as water, fluorinated solvents, supercritical fluids, or ionic liquids is also discussed.

Cluster Origin of the Solubility of Single-Wall Carbon Nanotubes

2005

The possibility of the existence of single-wall carbon nanotubes (SWNT) in organic solvents, in the form of clusters containing a number of SWNTs, is discussed. A theory is developed based on a bundletmodel for clusters, which enables describing the distribution function of clusters by size. Comparison of the calculated values of solubility with experimental data would permit obtaining energetic parameters characterizing the interaction of an SWNT with its surrounding in a solid phase or solution. Fullerenes and SWNTs are unique objects, whose behavior in many physical situations is characterized by remarkable peculiarities. Peculiarities in solutions show up in that fullerenes and SWNTs re…

ChemInform Abstract: Large Scale MOCVD Synthesis of Hollow ReS2Nanoparticles with Nested Fullerene-Like Structure.

2008

Topological effects of a rigid chiral spacer on the electronic interactions in donor-acceptor ensembles

2005

Two triads (donor-spacer-acceptor), etTTF-BN-C 6 0 (6) and ZnP-BN-C 6 0 (7), in which electron donors (i.e., exTTF or ZnP) are covalently linked to C 6 0 through a chiral binaphthyl bridge (BN), have been prepared in a multistep synthetic procedure starting from a highly soluble enantiomerically pure binaphthyl building block (1). Unlike other oligomeric bridges, with hinaphthyl bridges, the conjugation between the donor and the acceptor units is broken and geometric conformational changes are facilitated. Consequently, distances and electronic interactions between the donor and C 6 0 are drastically changed. Both donor-spacer-acceptor (D-s-A) systems (i.e., 6 and 7) exhibit redox processes…

Self-Assembly-Directed Organization of a Fullerene–Bisporphyrin into Supramolecular Giant Donut Structures for Excited-State Charge Stabilization

2021

Functional materials composed of spontaneously self-assembled electron donor and acceptor entities capable of generating long-lived charge-separated states upon photoillumination are in great demand as they are key in building the next generation of light energy harvesting devices. However, creating such well-defined architectures is challenging due to the intricate molecular design, multistep synthesis, and issues associated in demonstrating long-lived electron transfer. In this study, we have accomplished these tasks and report the synthesis of a new fullerene–bis-Zn-porphyrin e-bisadduct by tether-directed functionalization of C60 via a multistep synthetic protocol. Supramolecular oligom…

Theoretical prediction of the electronic properties of silicon fullerenes

1994

Summary form only given. High symmetry silicon clusters present currently intense interest because of the possibility they present properties similar to those displayed by fullerenes. Thermodynamic studies have shown that the buckminsterfullerene structure of Si6o is much more stable than other suggested structures. We present here a detailed investigation of the structure and electronic properties of silicon cluster analogous to fullerenes. We have made use of AMI method to obtain reliable geometrical parameters. The calculated valence effective Hamiltonian (VEH) electronic structures are used to predict ionization potentials, electron affinities, HOMO-LUMO energy gaps and first allowed tr…

A screening study on the fate of fullerenes (nC60) and their toxic implications in natural freshwaters

2013

Increasing usage of fullerenes (C60) increases their opportunities to be released into the environment. For risk assessment, it is important to understand the environmental fate and ecotoxicological effects of C60. In the present study, fullerene settling was measured during a 1-yr period with 4 different lake waters and an artificial freshwater, and Daphnia magna immobilization and fullerene accumulation was also measured in each of the lake waters. Depending on the characteristics of the lake waters, fullerenes either exhibited extended water stability or settled rapidly; in all waters, there was a fraction that remained stable after 1 yr. Water stability was affected by the quality and m…

Piezoresistive Sensors from Bithiophene-fulleropyrrolidine Bisadducts Thin-Films

The phenomenon of piezoresistivity in materials is based on the separation of conductive domains triggered by mechanical strains, resulting in a variation of the electrical resistance.1 This property is at the core of sensors for wearable electronics, e-skins, human motion detectors and machine learning devices.2 Fundamental requirements include lightness, good transparency, high flexibility and sensitivity to tiny deformations. However, the fabrication of a system integrating all these features is challenging. Herein, we show a semitransparent piezoresistive sensor realized by an electropolymerized bithiophene‐fulleropyrrolidine bisadduct onto ITO/PET3 (see Figure 1a). The good outcome of …

Substrate templating guides the photoinduced reaction of C60on calcite

2014

cited By 7; International audience; A substrate-guided photochemical reaction of C60 fullerenes on calcite, a bulk insulator, investigated by non-contact atomic force microscopy is presented. The success of the covalent linkage is evident from a shortening of the intermolecular distances, which is clearly expressed by the disappearance of the moiré pattern. Furthermore, UV/Vis spectroscopy and mass spectrometry measurements carried out on thick films demonstrate the ability of our setup for initiating the photoinduced reaction. The irradiation of C60 results in well-oriented covalently linked domains. The orientation of these domains is dictated by the lattice dimensions of the underlying c…

Distribution of fullerenes (nC60) between sediment and water in freshwaters

2014

Abstract Depending on environmental conditions, fullerenes (nC 60 ) have the potential to settle to the bottom sediments. In this study the distribution of nC 60 was investigated in the labile zone between sediment and water. Three freshwater–sediment systems representing oligohumic, mesohumic, and polyhumic lakes with varying sediment composition and structure were used to investigate the target of fullerenes. The largest portion of water suspended fullerenes was found in the sediment, but a part re-suspended relatively quickly to water-stabile particles associated with natural particles. Rapid initial re-suspending was followed by a slower one offering a continuous pathway to the water ph…