Surfactant-Templated Synthesis of Polypyrrole Nanocages as Redox Mediators for Efficient Energy Storage

Abstract

Preparation of conducting-polymer hollow nanoparticles with different diameters was accomplished by surfactant templating. An anionic surfactant, namely sodium dodecylbenzenesulfonate, formed vesicles to template with the pyrrole monomer. Subsequent chemical oxidative polymerization of the monomer yielded spherical polypyrrole (PPy) nanoparticles with hollow interiors. The diameter of the hollow nanoparticles was easily controlled by adjusting the concentration of the surfactant. Subsequently, the size-dependent electrochemical properties of the nanoparticles, including redox properties and charge/discharge behavior, were examined. By virtue of the structural advantages, the specific capacitance (max. 326 F g−1) of PPy hollow nanoparticles was approximately twice as large as that of solid PPy nanospheres. The hollow PPy nanostructure can easily be used as a conductive substrate for the preparation of metal/polymer nanohybrids through chemical and electrochemical deposition. Two different pseudocapacitive metal-oxide clusters were readily deposited on the inner and outer surfaces of the hollow nanoparticles, which resulted in an increase in the specific capacitance to 390 F g−1. In addition, the hollow nanoparticles acted as a nanocage to prevent metal ion leaching during charge/discharge, thus allowing an excellent capacitance retention of ca. 86%, even following 10,000 cycles.

Ruthenium oxide–carbon-based nanofiller-reinforced conducting polymer nanocomposites and their supercapacitor applications

“…In general, nanofiller materials enhance the performance of nanocomposites in various applications [114]. Ann et al [115] reported PPy hollow nanoparticles as the specific capacitance of C sp = 326 Fg −1 , which had two times higher than PPy. Its charge/discharge capacitance retention was obtained to be 86% even following 10.000 cycles.…”

Recent Advances in Nanostructured Conducting Polymers: from Synthesis to Practical Applications

“…Note that molecular templating is not only used to control the morphology of the resultant nanoparticles [66], it also affects the doping state of the CPs, which determines the electrical properties [67]. A recent notable example of such a formation mechanism is outlined in Figure 7.…”

“…The fabrication of these hybrids can be commonly achieved via the combination of CPs and inorganic species in the nanometer regime, as discussed above. A notable example is manganese oxide (MnO x )/CP nanohybrids [51,67,111,112]. Because MnO x can act as a reactive template in an acidic medium for the chemical polymerization of CP, direct CP nanocoating has been made on the surface of MnO x .…”

“…A variety of electrode materials have been designed and tested so far, including CP nanomaterials. As a recent remarkable example, PPy hollow nanoparticles were simply prepared using surfactant templates and their performance as the electrode for electrochemical capacitors was examined ( Figure 13) [67]. The hollow nanoparticles served as a nanocage to prevent metal ion leaching during charge/discharge, thus allowing excellent capacitance retention.…”

Nanoparticle-Mediated Physical Exfoliation of Aqueous-Phase Graphene for Fabrication of Three-Dimensionally Structured Hybrid Electrodes

“…In addition, the use of conducting polymers in a variety of applications (including electrochemical capacitors) has been extensively explored 12 13 14 15 16 17 ; this is because of the ease of synthesis and functionalization, reversible redox properties, and flexibility of these materials. In order to further improve their properties, considerable effort has been devoted to tailoring the sizes and morphologies of the nanoscale components of conducting polymers 18 19 20 21 .…”