Catalytic hydrogen storage in cerium nickel and zirconium (or aluminium) mixed oxides

Interaction of hydrogen with a series of cerium nickel and zirconium (or aluminium) mixed oxides CeM 0.5 Ni x O y ( M = Zr or Al, 0 ⩽ x ⩽ 3 ) has been studied in the 50–800 °C temperature range. Hydrogenation of 2-methyl-1,3-diene (isoprene) under helium flow in the absence of gaseous hydrogen is used to reveal and titrate reactive hydrogen species present in the solid previously treated under H 2 at various temperatures. The CeM 0.5 Ni x O y mixed oxides are large catalytic hydrogen reservoirs and among the solids studied, the highest amount of hydrogen (about 10 wt%, 540 g/L) is stored in CeZr 0.5 Ni 1 O y pretreated in H 2 at about 200 °C. Compared to the binary mixed oxides CeNi x O y , the presence of M allows to increase the hydrogen storage and give a better stability to the system, in particular, with temperature. Different physico-chemical techniques (TPR, TGA …) have been used to characterize the solids studied.