Oxidation−Reduction Reaction Driven Approach for Hydrothermal Synthesis of Polyaniline Hollow Spheres with Controllable Size and Shell Thickness

Different polyaniline (PANI) micro/mesostructures have been synthesized by one-pot polymerization of aniline using hydrogen peroxide (H2O2) as oxidant and Fe3+ as catalyst under hydrothermal conditions. Well-defined PANI hollow spheres with relatively uniform sizes and controllable shell thickness can be prepared in case of low concentrations of monomer and oxidant. The oxidation−reduction reaction between the benzenoid unit and O2 is a driving force for the formation of hollow spheres. This approach provides a unique route for the preparation of well-defined PANI hollow spheres in the absence of any sacrificial templates and organic surfactants and can be potentially extended to synthesize other polymer hollow spheres.