Synthesis and characterization of Cu-Al layered double hydroxides

A series of Cu-Al hydrotalcite-like layered compounds has been synthesized by coprecipitation using metal nitrate precursors and sodium carbonate. The Cu/Al atomic ratio was varied between 0.5 and 4. The dried precipitates we re characterized by powder X-ray diffraction (XRD) and thermogravimetric an alysis (TGA). The crystalline hydrotalcite-like phase was present as major component in all precipitates, the first time such crystalline phase was ob served in the precipitates of the constituent metals ratio as low as 0.5. T he malachite phase was also observed in variable amounts, and it became amo rphous at low copper content. (C) 2001 Elsevier Science Ltd. All rights res erved.