Regarding the use of hydrogen in fuel cell for mobile or stationary applications, metal hydrides can offer a high hydrogen volume capacity and a safe alternative compared with liquid storage or with compressed gas. Among the metal hydrides, magnesium is considered as one of potential hydrogen storage materials because of its high capacity (7.6 wt%), lightweight and low cost. However, high work temperature, slow reaction kinetics and hard activation process limit the practical application of Mg-based hydrides. Recently, the high energy ball milling was successfully introduced to prepare hydrogen storage materials. In this work, MgH2 catalyzed with Ni nanoparticles prepared by planetary type ball milling under hydrogen atmosphere (10 bar) was investigated. As the results, small amount of 1 mol% Ni in nanometer scale acts as a suitable catalyst for improvement the kinetics of MgH2 which could absorp 5.3 wt% of hydrogen within 5 minutes at 300°C. It is obvious that small amount has much better as catalyst in nanoparticle size and at the same time allowed to reduce the milling process in short time.
hydrogen storage, magnesium, metal hydrides, ball milling
