| 초록 |
In recent years, serious environmental concerns regarding pollution have emerged. Among the many metals that are capable storing hydrogen, Mg is one of the most promising candidates due to its high hydrogen storage capacity(7.6 wt.%), abundant resources, and relatively low cost. However, the commercial applications of the Mg hydrides are currently hinder by its high absorption/desorption temperature, and very slow reaction kinetics. Alloying or compound formation with other elements is one of the main approaches for thermodynamically destabilizing MgH2. A classic example is the combination of Mg with Ni to form theintermetallic compound Mg2Ni. Mg2Ni can reversibly absorb ~3.6 wt.% hydrogen by forming Mg2NiH4. However, desorption temperature is still too high and the kinetics are rather sluggish. The absorption/desorption kinetics of Mg2Ni could be significantly enhanced by introducing different metals M (M=V, Cr, Fe, Co, Cu or Zn)at the Ni sites. In this study, 20wt.% CaO was added to Mg2Ni, the thermodynamic and the kinetic properties of dehydrogenation in the Mg-Ni-CaO system was investigated. The powder synthesized was characterized by XRD, SEM. The hydrogenation behaviors were evaluated by using a Sievert’s type automatic PCT apparatus. |
