Preparation of Layered Double-Hydroxide Nanomaterials with a Uniform Crystallite Size Using a New Method Involving Separate Nucleation and Aging Steps

In particle formation, the method can be just as important as the chemical reaction involved. A new method of synthesizing hydrotalcite-like layered double hydroxides (LDHs) of the type [Mg1-xAlx(OH)2]x+(CO32-)x/2·yH2O (x = 1.7−3.3) is reported. The key features of this method are a very rapid mixing and nucleation process in a colloid mill followed by a separate aging process. The properties of the resulting LDHs are compared with those of materials produced using the conventional coprecipitation process at constant pH. The compositions and structural parameters of the materials synthesized using the two routes are very similar, although the crystallinity is slightly higher for the LDHs produced using the new…