Hollow Polyaniline Helical Nanobelts toward Efficient Electrochemical Energy Storage and Adsorption Performance

We reported a simple method with the oligomers of target products as a synthetic template to fabricate hollow polyaniline (PANI) helical nanobelts by chemical oxidation of aniline in a hydrochloric acid/isopropyl alcohol/water mixed solvent. The hollow oligoaniline (OANI) helical nanobelts generated in the early reaction stage were identified as sacrificial templates to induce the growth of hollow PANI helical nanobelts. The hollow PANI helical nanobelts with a large specific surface area were more capable of adsorbing many electrolyte ions to participate in Faraday electrode reactions, and then the PANI exhibited high utilization efficiency, leading to a high specific capacitance up to 688 F/g at a scan rate of 5 mV/s and long cycle life (81.6% retention after 1000 cycles). The symmetric supercapacitor device was assembled by two pieces of hollow PANI helical nanobelt electrodes, which possessed a high energy density of 14.37 Wh/kg at a power density of 500 W/kg. The hollow PANI helical nanobelts contained many amino and imino groups, which provided a large number of adsorption sites for the adsorption of rhodamine 6G molecules. In addition, the adsorption kinetics of the dye in the presence of doped PANI was also determined.