Composite MoS 2 /carbon nanotube material has been produced by hydrothermal decomposition of a mixture of multiwall carbon nanotubes (CNTs) and a water solution of ammonium molybdate and thiourea. Transmission electron microscopy and Raman spectroscopy showed formation of MoS 2 layers on the CNT surface and MoS 2 flakes. X-ray photoelectron spectroscopy revealed a downshift of C 1s peak of the composite as compared to the pristine CNT sample that was related to charge transfer between the components. This fact was confirmed by near-edge X-ray absorption fine structure spectroscopy which detected a decrease of intensity of π* resonance in the C K-edge spectrum after the MoS 2 deposition. Quantum-chemical calculations of a CNT@MoS 2 model showed a positive charging of the CNT surface. Comparison of field emission characteristics of CNTs and the composite indicated lowering of the voltage threshold in the latter sample.

Multi‐walled carbon nanotubes (CNTs) and nitrogen‐doped carbon (CNx) nanotubes have been synthesized by the aerosol‐assisted chemical vapour deposition (CVD) method. The samples were prepared from toluene and acetonitrile taken in different proportion. The structure of CNTs and CNx nanotubes was compared using first‐ and second‐order Raman spectra. The disorder‐induced D band was found to up‐shift with increase of the acetonitrile fraction. The ID/IG and IG′/IG ratios showed the opposite dependence on the doping level of CNTs. Both kinds of the substitute nitrogen: graphitic‐like and pyridinic‐like contribute to the disorder in CNx nanotube layers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)