Chlorosulfonic acid assisted the exfoliation of MoS2 and WS2 resulting in retaining their semiconducting 2H-phase, sharply contrasting the semiconducting-to-metallic phase-transition observed with the currently available exfoliation techniques.

Carbon nanotubes are considered as molecular wires exhibiting novel properties for diverse applications including medicinal and biotechnological purposes. Surface chemistry on carbon nanotubes results on their solubilization in organic solvents and/or aqueous/physiological media. Herein, we will present how interfacing such novel carbon-based nanomaterials with biological systems may lead to new applications in diagnostics, vaccine and drug delivery. Recent developments in this rapidly growing field will be presented thus suggesting exciting opportunities for the utilization of carbon nanotubes as useful tools for biotechnological applications. Emphasis will be placed in the integration of biomaterials with carbon nanotubes, which enables the use of such hybrid systems as biosensor devices, immunosensors and DNA-sensors.

Structural, optical, electrical, and optoelectronic properties, as well as prototype light-emitting devices, are being reported for the two-dimensional (quantum well) organicÀinorganic hybrid semiconductor systems based on the organic cations CH 3 -(CH 2 ) 7 CHdCH(CH 2 ) 8 NH 3 þ (OL) and on the inorganic networks formed out of MX 4 2À anions, where M = Pb and X = I, Br, and Cl. These new crystalline compounds show extremely intense excitonic bands at chemically controllable positions in the ultravioletÀvisible spectral region, with excitonic binding energies of more than 180 meV at room temperature. These novel properties render them as strong potential candidates in optoelectronic applications, comparable to the artificial low-dimensional systems. Prototype light-emitting devices (LED) based on the above-mentioned compounds exhibit naked eye electroluminescence, in some cases, semicontinuous operation, for the first time at room temperature. In addition, these devices operate at relatively low voltages and are readily realized. Because of the enhanced film-forming and degradation-resistant properties of the active materials, the device functionality is being exhibited for weeks. Thus, it is expected that this particular reported synthetic route of hybrid organicÀinorganic semiconductors could provide cost-effective materials for novel optoelectronic devices. Moreover, the properties of some composite systems of the type (CH 3 NH 3 ) nÀ1 (OL) 2 Pb n X 3nþ1 are being reported briefly.

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The covalent grafting through a rigid ester bond of a dimeric porphyrin [(H 2 P) 2 ] and carbon nanohorns (CNHs) was accomplished. The newly formed CNH−(H 2 P) 2 hybrid was found to be soluble or dispersible in several organic solvents. Application of diverse spectroscopic techniques verified the successful formation of the CNH−(H 2 P) 2 hybrid material. In addition, thermogravimetric analysis revealed the amount of (H 2 P) 2 loading onto CNHs, and TEM studies showed the characteristic secondary spherical superstructure morphology of the hybrid material. Efficient fluorescence quenching of (H 2 P) 2 in the CNH−(H 2 P) 2 hybrid suggests that photoinduced events occur from the photoexcited (H 2 P) 2 to CNHs. Nanosecond transient absorption spectroscopy revealed the formation of transient species such as (H 2 P) 2•+ and CNH •− by photoinduced charge separation in CNH−(H 2 P) 2 . Additional proof for the photoinduced charge-separated state CNH •− −(H 2 P) 2•+ was obtained, from which the electron mediates to added hexyl viologen dication (HV 2+ ). Finally, the CNH−(H 2 P) 2 was adsorbed on nanostructured SnO 2 electrode, to construct a photoactive electrode, which reveals photocurrent and photovoltage responses with an incident photon-to-current conversion efficiency value as large as 9.6%, without the application of any bias voltage.

The covalent attachment of carbon nanohorns (CNHs) to α‐5‐(2‐aminophenyl)‐α‐15‐(2‐nitrophenyl)‐10,20‐bis(2,4,6‐trimethyl‐phenyl)‐porphyrin (H2P) via an amide bond is accomplished. The resulting CNH–H2P nanohybrids form a stable inklike solution. High‐resolution transmission electron microscopy (HRTEM) images demonstrate that the original dahlia‐flowerlike superstructure of the CNHs is preserved in the CNH–H2P nanohybrids. Steady‐state and time‐resolved fluorescence studies show efficient quenching of the excited singlet state of H2P, suggesting that both electron and energy transfer occur from the singlet excited state of H2P to CNHs, depending on the polarity of the solvent. In the case of electron transfer, photoexcitation of H2P results in the reduction of the nanohorns and the simultaneous oxidation of the porphyrin unit. The formation of a charge‐separated state, CNH•––H2P•+, has been corroborated with the help of an electron mediator, hexyl‐viologen dication (HV2+), in polar solvents. Moreover, the charge‐separated CNH•––H2P•+ states have been identified by transient absorption spectroscopy.

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The essential oil and a number of extracts of Rosmarinus officinalis L. in solvents of increasing polarity were isolated, and their components identified and tested as pest control agents. Ethanol and acetone extracts attract grape berry moth Lobesia botrana. However, none of the extracts had a significant effect on western flower thrips Frankliniella occidentalis, which is attracted by 1,8-cineole, a major essential oil component.