Layered Double Hydroxide Intercalate of Metal-Chelate Complex—a Novel Precursor for the Formation of a Mixed Metal Oxide

Abstract

The reaction of a nitrilotriacetate-intercalated Mg-Al layered double hydroxide in a lanthanum nitrate solution is studied. La³⁺ is incorporated into the interlayer through the formation of a chelate complex. NO₃ ⁻ is also taken up as a charge-balancing anion. During chelation the interlayer repeat increases from 11.9 A to 13.9 A. Chemical analysis suggests that 1:1 and 1:2 metal:chelate complexes are formed within the interlayer. Calcination of the La³⁺-containing double hydroxide results in the formation of LaAlO₃.

Key Words:

• Intercalation
• LDH
• Anionic clay
• Chelate
• Lanthanum Oxide
• Thermal decomposition