III International Conference

PP-I-56size of metals encapsulated in carbon matrix varies from few nanometers up to tensnanometers for different metals and regimes of preparation, while for a given composite theparticle size distribution is rather narrow.To clarify the catalytic ability of nanocomposite Ni@C am we used the reaction ofmagnesium hydrogenation in the process of mechanical milling of Mg in hydrogenatmosphere at room temperature. The hydrogenation of Mg alloys at mechanical activation inH 2 atmpsphere is known to require the introduction of a catalyst. Mechanical activation of Mgwith an addition of the well-known catalyst V 2 O 5 allows us to synthesize 50% of MgH 2hydride after 7 h of milling (in comparison with 60 h required to do the same withoutcatalysts). The abnormally high catalytic activity was observed when the carbon-encapsulatednickel was applied as a catalyst in hydrogenation reaction at ball-milling of Mg in hydrogenatmosphere. The rate of Mg hydrogenation in the appearance of Ni@C catalyst exceeds atleast one order magnitude than the utmost catalyst on the base of V 2 O 5 .In the report we will discuss the possible mechanisms of catalytic activity of Ni@C m forformation of MgH 2 during the mechanical activation in H 2 atmosphere and suggest theperspectives of the practical applications for Me@C am nanocomposites for other purposes.Acknowledgments.Authors express gratitude to our colleagues Dr. Yu.S .Ponosov, Dr N.N. Schegoleva, DrV.S. Gaviko for the sample characterizations.106