Chromate intercalation in Ni–Zn layered hydroxide salts

An acetate-intercalated Ni–Zn layered hydroxide salt (LHS) was exchanged with chromate anions, achieving a rather large oxometalate concentration, which almost completely balanced the positive charges of the layers, as concluded from element chemical analysis, powder X-ray diffraction, and FT-IR spectroscopy results.Thermal decomposition of the solid led to dehydration and chromate anion grafting, followed by dehydroxylation of the host and reduction of the chromate anions. The solid then lost the layer structure, forming solids with large micro and mesoporosity, which corresponded to poorly crystallized (Zn, Ni)–Cr spinels, as well as nickel and zinc oxides.