Synthesis and assembly of oligoaniline for hierarchical structures within stable and mild acid system

Oligoanilines (OANI) with hierarchical structures were synthesized via chemical oxidative polymerization within a stable weak-acid system. Acetic acid was used as the buffer and dopant, and low concentration of ammonium peroxydisulfate (APS) and aniline were added to tune the pH value and to obtain different morphologies. With the pH value varied from 4.26 to 4.11 to 3.26, flake-like structure, flower-like morphology consisted of dozens of nanoflakes and lath-like structure composed of parallel alignment of nanorods are produced, respectively. Under different reaction conditions, OANI with different chemical structures are formed and simultaneously assemble into hierarchical structures. The formation mechanism of these hierarchical structures is proposed. These hierarchical OANI were used as support to load Mo catalyst and flower-like OANI/Mo catalyst shows a good property in epoxidation of cyclooctene.