Facile synthesis of hollow spheres of sulfonated polyanilines

Core-shell type sulfonated polyaniline (SPAN)-iron oxide nanoparticles (IONP) composites (IONP-SPAN-NC) were prepared. The interactions between the positve and negative charges on the surface of IONP and sulfonic acid and amine groups, respectively, in SPAN form the basis for core-shell structure for the composite. Sulfonated polyaniline hollow spheres (SPAN-HS) were generated by preferential dissolution of IONP from the composite. TEM photograph of IONP-SPAN-NC reveals that IONPs are 'glued' to SPAN chains and hollow spheres are formed on removal of IONP. Morphology, optical and magnetic properties of the IONP-SPAN-NC and SPAN-HS were compared.