Chemical design of a smart chitosan-polypyrrole-magnetite nanocomposite toward efficient water treatment.

A magnetic chitosan-polypyrrole-magnetite (Cs-PPy-Fe3O4) nanocomposite is prepared in a simple one-step method via in situ chemical polymerization of pyrrole using anhydrous FeCl3 as an oxidant in the presence of Cs. Magnetic Fe3O4 nanoparticles of size in the range of 10-20 nm are successfully introduced into the Cs-PPy matrix. Adsorption of an anionic dye (acid green 25, AG) from aqueous solution into the Cs-PPy-Fe3O4 nanocomposite is investigated. The nanocomposite exhibits high adsorption capacity compared to PPy and Cs themselves. After the adsorption, the Cs-PPy-Fe3O4 nanocomposite is easily separated from the reaction solution using an external magnet, which is very useful for practical applications.