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CNT arrays have been synthesized by the high temperature pyrolysis of fluid hydrocarbon - p-xylole [С8Н10] (CVD-method) in the presence of volatile catalysts - ferrocene [Fe(C5H5)2] at atmospheric pressure with the use of Ar as a gas-carrier. CNTs were deposited to the surfaces of Si wafer and tubular-type quartz reactor of specially constructed equipment for realization CVD method. In order to vary different factors influencing the parameters of CNTs a special electromechanical injector have been developed, permitting to vary over a wide range the hydrocarbon types, the rate of fluid reagents injection into the synthesis zone and the percentage ratio of catalyst in the hydrocarbon solution.
The CNTs synthesis was performed in the regime of the preferable growth on Si surface at the atmospheric pressure under the following conditions: concentration of ferrocene in p-xylole – 10 %, solution injection rate - 1,00 mlmin-1, temperature - 870 °C, Ar flow rate - 100 cm3min-1 and the process duration – 5 min.
Complex investigation of crystalline structure, composition and magnetic properties of obtained CNT arrays have been performed. It was observed that under the realized regimes the vertically oriented closely pact CNTs were formed with the same structure and composition on the Si and quartz tube surfaces.
By different experimental methods the composition of synthesized composites was determined. It is C-Fe3C-Fe5C2–Fe mixture. The dimensions of Fe3C, Fe5C2 и Fe stuff of CNTs have enough large dispersion: 5-40 nm.
X-ray analysis, measurements of specific magnetization and results of nuclear gamma-resonance showed that Fe3C constitute more than 90% of the hole CNTs stuff. The determined Fe3C elementary cell parameters are: а = 0.452 nm; b = 0.508 nm; c = 0.672 nm.
The measurements of the specific magnetization showed that synthesized CNTs with the Fe3C-Fe5C2-Fe staff poses reversible magnetic properties in the temperature range 78К ≤ Т ≤ 720К.
Determined effective magnetic fields on the nucleus 57Fe incoming to the staff composite, which showed that Fe nanoparticle encapsulated into CNT exposes super paramagnetic properties.
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