Designed nanostructures of clay for controlled adsorption of organic compounds.

The utilization of smectite clay, swelling layered silicate, as scaffolds for designing functional nanostructures was overviewed. Surface modification of smectites with organoammonium ions has given hydrophobic and microporous nature to uptake nonionic organic contaminants from environments. The states of the adsorbed nonionic organic compounds have been altered and varied by the modification of smectites as shown by the controlled release and specific catalytic reactions. Cationic species have been easily concentrated on smectites from aqueous phase and the states (orientation and distribution) have been controlled by the co-adsorption of both cationic and nonionic species. The functions of smectite-organic intercalation compounds derived from the precisely controlled nanostructures were introduced in this review.