Studies on hydrogen storage alloy, Mg2Ni: catalytic activity and XPS

Abstract

Catalytic activity of hydrogen storage alloy, Mg₂Ni and modified Mg₂Ni(O-Mg₂Ni) has been studied using decomposition of 2-propanol as test reaction. Besides dehydrogenation activity, Mg₂Ni shows some activity towards the formation of condensation products, viz. mesityl oxide, isobutyl methyl ketone and diisobutyl ketone. XRD of spent Mg₂Ni indicate disproportionation of Mg₂Ni to MgO, Ni and NiO under reaction conditions, while XP spectra show coke formation on its surface. On O-Mg₂Ni the activity is reproducible with only acetone as the product. The activity, selectivity and stability have been explained based on the difference in their surface composition as revealed by XPS studies.