Core/shell structured halloysite/polyaniline nanotubes with enhanced electrochromic properties

Novel halloysite (HNT)/polyaniline (PANI) nanocomposites are fabricated by controllable in situ chemical polymerization for electrochromic applications. The nanocomposites with different morphologies can be obtained simply by controlling the relative proportions of aniline (ANI) monomers and HNTs in the chemical polymerization system. "Adsorption'' is proposed to account for the preferential growth of PANI along HNT nanotubes to form a core/shell structure. The films casted by the nanocomposites exhibited remarkably enhanced electrochromic performances. When compared with pure polyaniline, nanocomposite films possess a faster response time (1.0 s for bleaching and 3.0 s for coloring), higher optical contrast (60.5%), and more remarkable switching stability (over 500 cycles). The unique nanocomposites pave the way for developing new functional materials with enhanced properties for new applications.