Enhanced Hydrogen Storage Properties of MgH2 by The Addition of PdCl2 Catalyst
School of Ocean Engineering, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia
*Email Address : mohammadismail@umt.edu.my
Abstract : The effect of PdCl2 on the hydrogen storage properties of MgH2 has been investigated in the present study. The results indicated that the desorption temperature was reduced after the addition of PdCl2 and 20 wt % doping amount showed the best performance in terms of onset dehydrogenation temperature as compared with undoped MgH2. The desorption temperature of MgH2 + 20 wt % PdCl2 was decreased about 275 °C compared to 375 °C and 420 °C for as-milled and as-received MgH2, respectively. The de/rehydrogenation kinetics of the doped MgH2 also improved after doping with PdCl2. From the Kissinger analysis, the apparent activation energy, Ea, for hydrogen desorption was reduced from 142 kJ/mol for as-milled MgH2 to 99 kJ/mol after the addition of 20 wt % PdCl2. From the X-ray diffraction result, it is believed that the formation of the new species of PdH0.778, MgCl2 and Mg6Pd during the ball milling or de/rehydrogenation process might actually be responsible for the catalytic effects, and thus, further enhanced the hydrogen storage properties of the MgH2.
Keywords : hydrogen storage,magnesium hydride,catalytic effect