Functionalization of Layered Double Hydroxides with Aminoalkylphosphonic Acids to Yield Water-Dispersible Plate-Shaped Nanoparticles

Keywords:
layered double hydroxides, functionalization, plate-shaped nanoparticles, water-dispersible

Abstract:
Mg3Al-NO3-LDH (layered double hydroxide) has been functionalized with amino¬alkyl¬phosphonic acids, e.g. aminoethylphosphonic acid. The resulting product can be dispersed, and fully delaminated in water, to form a stable, transparent sol of plate-shaped nanoparticles. The functionalization resulted in positively charged water-dispersible plate-shaped nanoparticles. Samples were characterized both in powder form and as a colloidal solution with X-ray diffraction, atomic force microscopy, dynamic light scattering, FT-IR and elemental analysis (CHN). Characterization data confirm that the functionalized particles can be delaminated in water at high concentrations to give nanosheets with dimensions of approximately 30 x 30 x 1.7 nm. Furthermore, the particles can be dispersed in water even after being completely dried, which is not usually the case for nano¬particles. The main target applications are water-based formulations and nanocomposites.

Nanotech 2008 Conference Program Abstract