Abstract
Nickel aluminum double hydroxides, Ni1-xAlx (OH) 2 (CO3) x/2·mH2O, were prepared from a hexaamminenickel (II) complex solution by the addition of mixed solutions of aluminum nitrate and sodium hydroxide. The crystallinity of the products was better than that of the double hydroxides prepared by a conventional coprecipitation method. Based on the relationship between the layer spacing and the atomic fraction Al/(Al + Ni) in the products [=R (pro)], the range for the formation of the single phase products was determined to be 0.19≤R (pro)≤0.33. In this range the layer spacing diminished with the increase in R (pro). IR and DTA results also indicated the variation in the layer charge caused by the aluminum substitution. The anion exchange capacity was 1.5-2.6 meq/g within the solid solution range. The thermal behavior of the products was also investigated.
