High-Power Abiotic Direct Glucose Fuel Cell Using a Gold-Platinum Bimetallic Anode Catalyst.

We developed a high-power abiotic direct glucose fuel cell system using a Au-Pt bimetallic anode catalyst. The high power generation (95.7 mW cm) was attained by optimizing operating conditions such as the composition of a bimetallic anode catalyst, loading amount of the metal catalyst on a carbon support, ionomer/carbon weight ratio when the catalyst was applied to the anode, glucose and KOH concentrations in the fuel solution, and operating temperature and flow rate of the fuel solution.

Semireduction of Alkynes Using Formic Acid with Reusable Pd-Catalysts.

The treatment of PdCl with KCO and HCOH in dioxane gives black precipitates, which are an effective catalyst for the semireduction of alkynes to alkenes using formic acid as a reductant. Even 0.05 mol % Pd promoted the reduction reaction of tolane in high yield with high selectivity.

Not nanocarbon but dispersant induced abnormality in lysosome in macrophages in vivo.

The properties of nanocarbons change from hydrophobic to hydrophilic as a result of coating them with dispersants, typically phospholipid polyethylene glycols, for biological studies. It has been shown that the dispersants remain attached to the nanocarbons when they are injected in mice and influence the nanocarbons' biodistribution in vivo. We show in this report that the effects of dispersants also appear at the subcellular level in vivo.

Ultrastructural localization of intravenously injected carbon nanohorns in tumor.

Nanocarbons have many potential medical applications. Drug delivery, diagnostic imaging, and photohyperthermia therapy, especially in the treatment of tumors, have attracted interest. For the further advancement of these application studies, the microscopic localization of nanocarbons in tumor tissues and cells is a prerequisite.

Carboxylation of thin graphitic sheets is faster than that of carbon nanohorns.

Globular aggregates of carbon nanohorns (CNHs) often contain graphite-like thin sheets (GLSs), and providing different functions to CNHs and GLSs would expand the possible applications of the CNH-GLS aggregates. We show that the GLS edges can be carboxylated selectively by immersing the aggregates in an aqueous solution of H2O2 at room temperature for 1 hour. The presence of carboxyl groups was confirmed by temperature-programmed desorption mass spectroscopy measurements, and their amounts were evaluated using thermogravimetric analysis.

Benzyne cycloaddition onto carbon nanohorns.

A facile approach for the covalent functionalization of carbon nanohorns (CNHs) based on the benzyne cycloaddition reaction is presented. The benzynes were in situ generated from either anthranilic acid by decomposition of the internal benzenediazonium-2-carboxylate or from 2-(trimethylsilyl)-phenyl triflate by fluoride ion attack at the silicon atom followed by displacement of the trimethylsilyl group under mild conditions. Moreover, the functionalization reaction was tested and performed under conventional conditions as well as under microwave irradiation.

Microwave-assisted functionalization of carbon nanohorns via [2+1] nitrenes cycloaddition.

The microwave-assisted functionalization of carbon nanohorns (CNHs) via [2+1] nitrenes cycloaddition, providing well dispersible hybrid materials possessing aziridino-rings covalently grafted onto the graphitic network of CNHs, was accomplished, while condensation of hydroxy-functionalized CNHs with thioctic acid, furnishing an endocyclic disulfide bond extended from the aziridino-rings, allowed the stabilization of Au nanoparticles.

Highly efficient field emission from carbon nanotube-nanohorn hybrids prepared by chemical vapor deposition.

Electrically conductive carbon nanotubes (CNTs) with high aspect ratios emit electrons at low electric fields, thus applications to large-area field emission (FE) devices with CNT cathodes are attractive to save energy consumption. However, the poor dispersion and easy bundling properties of CNTs in solvents have hindered this progress. We have solved these problems by growing single-walled CNTs (SWNTs) on single-walled carbon nanohorn (SWNH) aggregates that have spherical forms with ca.

Decoration of carbon nanohorns with palladium and platinum nanoparticles.

Carbon nanohorns (CNHs) have been decorated with palladium and platinum nanoparticles, which are prepared in-situ, with the aid of sodium dodecyl sulphate (SDS), by the self-regulated reduction of palladium acetate and chloroplatinic acid, respectively. The latter acts as a reducing agent for the metal ions, while at the same time, aids the solubilisation of CNHs. The soluble in polar media nanoPd-CNH and nanoPt-CNH hybrid materials have been characterised and morphologically evaluated by complementary microscopy, thermal and analytical techniques such as transmission electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, thermogravimetric analysis, UV-VIS-NIR and Raman spectroscopy.

Biodistribution and ultrastructural localization of single-walled carbon nanohorns determined in vivo with embedded Gd2O3 labels.

Single-walled carbon nanohorns (SWNHs) are single-graphene tubules that have shown high potential for drug delivery systems. In drug delivery, it is essential to quantitatively determine biodistribution and ultrastructural localization. However, to date, these determinations have not been successfully achieved.

Enhancement of in vivo anticancer effects of cisplatin by incorporation inside single-wall carbon nanohorns.

Cisplatin (CDDP) was incorporated inside single-wall carbon nanohorns with holes opened (SWNHox) by a nanoprecipitation method that involved dispersion of CDDP and SWNHox in a solvent followed by the solvent evaporation. The incorporated CDDP quantity increased from the previously reported value of 15 to 46%, and the total released quantity of CDDP also increased from 60 to 100% by changing the solvent from dimethylformamide to water. Concurrently, in vitro anticancer efficiency of CDDP@SWNHox increased to 4-6 times greater than that of the intact CDDP.

(Terpyridine)copper(II)-carbon nanohorns: metallo-nanocomplexes for photoinduced charge separation.

New metallo-nanostructured materials of carbon nanohorns (CNHs), within the family of elongated carbon nanotubes, have been prepared by the coordination of copper(II)-2,2':6',2' '-terpyridine (Cu(II)tpy) with oxidized carbon nanohorns (CNHs-COOH). The resulted CNHs-COO-Cu(II)tpy metallo-nanocomplexes have been characterized by diverse analytical spectroscopic tools and cyclic and differential pulse voltammetry. Scanning transmission electron microscopy (STEM), dynamic light scattering (DLS), and energy dispersive X-ray spectroscopy (EDX) measurements have been employed to probe the morphological characteristics and particle-size distribution of CNHs-COO-Cu(II)tpy as well as to investigate the elemental composition of the metallo-nanocomplex.

Controlling the incorporation and release of C60 in nanometer-scale hollow spaces inside single-wall carbon nanohorns.

We succeeded in large-scale preparation of single-wall carbon nanohorns (SWNH) encapsulating C60 molecules in a liquid phase at room temperature using a "nano-precipitation" method, that is, complete evaporation of the toluene from a C60-SWNH-toluene mixture. The C60 molecules were found to occupy 6-36% of the hollow space inside the SWNH, depending on the initial quantity of C60. We showed that the C60 in C60@SWNHox was quickly released in toluene, and the release rate decreased by adding ethanol to toluene.

In situ observation of carbon-nanopillar tubulization caused by liquidlike iron particles.

The tubulization process of amorphous carbon nanopillars was observed in situ by transmis-sion electron microscopy. Amorphous carbon nanopillars were transformed into graphitic tubules by annealing at 650-900 degrees C in the presence of iron nanoparticles. A molten catalyst nanoparticle penetrated an amorphous carbon nanopillar, dissolving it, and leaving a graphite track behind.

Energy-filtered electron diffraction and high-resolution electron microscopy on short-range ordered structure in GaAs(0.5)Sb(0.5).

Characteristic intensity distribution of diffuse scattering in III-V alloy semiconductor GaAs(0.5)Sb(0.5) epitaxially grown was observed by the energy-filtered electron diffraction method with [110] incidence.