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Thermal, Chemical and Radiation Treatment Influence on Hydrogen Adsorption Capability in Single Wall Carbon Nanotubes Michail Obolensky2, Andrew Kravchenko2, Vladimir Beletsky2, Yuri Petrusenko3, Valeriy Borysenko3, Sergey Lavrynenko3, Andrew Basteev1 and Leonid Bazyma1 1

National Aerospace University, Kharkov Aviation Institute “KhAI”, 17 Chkalov St., Kharkov, 61070, Ukraine 2 V.N. Karazin Kharkiv National University, 4 Svobody Sq., Kharkov, 61077, Ukraine 3 National Science Center - Kharkov Institute of Physics and Technology, 1 Akademicheskaya St., Kharkov, 61108, Ukraine. ABSTRACT The raw single wall carbon nanotubes (SWCNT) were chemically and thermally treated and then milled in ball mill. After this SWCNT were irradiated by electron beam with energy 2.3 MeV up to fluence 1014 e-/cm2 at room temperature. Then SWCNT were saturated with hydrogen at pressure 5 bar and quenching down to the temperature 78 K. The sorption capability was measured by means of mass-spectroscopy and volumetric methods. The double increasing of mass hydrogen content in electron bombarded SWCNT was showed comparatively with nonirradiated samples. INTRODUCTION The main methods of carbon nanotubes (CNT) synthesis give the formation of products mixture with different degree of defect, structure and dimensional properties. The results reproducibility remains the serious problem of CNT practical use. This problem is linked with the requirement to CNT to have the same or at least very clear properties after purification and separation procedure. Despite the fact that there are a lot of different technologies for CNT synthesis now none of the above technologies provide the results reproducibility. Thus the procedures of CNT purification and separation have the primary importance. As is well known the CNT thermal treatment enhance the hydrogen sorption capability sufficiently even at atmospheric pressure [1]. The chemical processing without thermal treatment can both enhance the hydrogen content as well decrease it [2]. The complex CNT treatment (chemical and thermal) are allow obtaining more significant values of sorption capabilities. The four times increasing of hydrogen percentage in comparison with non-treated samples was showed in [2] and hydrogen mass content was performed at the level more than 6 percent. Enough high values of hydrogen mass content at relatively low pressures were demonstrated in [2] and this fact could be linked with defects presence in nanotube wall structure. Formation of these dislocations could be explained by annealing procedure for example and they form the singular wall shape and surface roughness which are associated with heightened hydrogen atoms binding energy [2]. The recent investigations [3-5] showed that there is the perspective for CNT sorption capability enhancing due to especial dislocation formation in it structure by means of electron

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bombardment and Ȗ – quantum irradiation. The types of different dislocations which are appearing after SWCNT electron bombardment were considered especially in [