TY - JOUR A1 - Mach, Reinhard A1 - Klotz, Hans-Dieter A1 - Oleszak, Franz A1 - Maneck, Heinz-Eberhard A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner T1 - Synthesis and characterization of nanoscaled and nanostructured carbon containing materials produced by thermal plasma technology N2 - Single-walled carbon nanotubes (SWNT) and carbon nitride films are synthesized by a direct current (dc) arc discharge at slightly reduced pressure and by an inductively coupled r.f. plasma (ICP) at atmospheric pressure, respectively. By treatment with nitric acid SWNT are purified from by-products and characterized by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. ICP allows the deposition of carbon nitride films on steel substrate. The deposition of the films creates a relatively strong radial symmetric profile. The structure of the films are rather independent of the distance between substrate and plasma. Raman, Fourier transform infrared (FTIR), and energy dispersive X-ray (EDX) spectroscopy are used for analyzing the carbon nitride materials. T2 - 11th Conference on Applied Surface Analysis (AOFA) CY - Leipzig, Germany DA - 2000-09-24 KW - Single-walled carbon nanotubes KW - Carbon nitride films KW - Arc discharge KW - Inductively coupled r.f.plasma PY - 2001 DO - https://doi.org/10.1016/S0169-4332(01)00253-7 SN - 0169-4332 SN - 1873-5584 VL - 179 IS - 1-4 SP - 1 EP - 7 PB - North-Holland CY - Amsterdam AN - OPUS4-1023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meyer-Plath, Asmus A1 - Orts Gil, Guillermo A1 - Petrov, Sergej A1 - Oleszak, Franz A1 - Maneck, Heinz-Eberhard A1 - Dörfel, Ilona A1 - Haase, Oskar A1 - Richter, Silke A1 - Mach, Reinhard T1 - Plasma-thermal purification and annealing of carbon nanotubes N2 - We have developed a very fast and entirely gas-phase based purification technique for carbon nanotubes (CNT) that allows removing metal and metal oxide impurities with high effectiveness. CNT agglomerates from chemical vapor deposition (CVD) synthesis which contained carbon encapsulated catalysts were injected into an atmospheric plasma torch. Very high heating rates allow for quasi-instantaneous vaporization of catalyst particles. This way, metal vapors are hyposized to break mechanically instable encapsulations and effuse from incomplete ones faster than thermally induced graphitization stabilizes such particle encapsulations. The ash content of multi-walled (MW) CNT samples was reduced to less than 15% of the initial value within a few milliseconds. Also the metal content of single-walled (SW) CNT agglomerates was significantly reduced. Repeated injection of CNT agglomerates into the plasma torch resulted in higher-purity products of improved structural integrity and increased oxidation resistance. PY - 2012 DO - https://doi.org/10.1016/j.carbon.2012.04.049 SN - 0008-6223 SN - 1873-3891 VL - 50 IS - 10 SP - 3934 EP - 3942 PB - Pergamon Press CY - New York, NY AN - OPUS4-25986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -