Chemical synthesis of hollow sea urchin like nanostructured polypyrrole particles through a core–shell redox mechanism using a MnO2 powder as oxidizing agent and sacrificial nanostructured template

Abstract

Chemical synthesis of hollow sea urchin like nanostructured polypyrrole particles through a core-shell redox mechanism using a MnO2 powder as oxidizing agent and sacrificial nanostructured template. Synthetic Metals, Elsevier, 2013, 175, pp.192-199. 10.1016/j.synthmet.2013 1 Chemical synthesis of hollow sea urchin like nanostructured polypyrrole particles through a core-shell redox mechanism using a MnO 2 powder as oxidizing agent and sacrificial nanostructured template AbstractHollow sea urchin shaped nanostructured polypyrrole powder was successfully synthesized chemically in an acidic medium through a core-shell redox mechanism by using a nanostructured MnO 2 powder as oxidizing agent and sacrificial template simultaneously. The morphology and the structure of MnO 2 powder based reactant and produced polypyrrole powder were characterized respectively by using FEG-SEM, TEM, EDX and XRD techniques, which led us to demonstrate clearly the formation of hollow and open microparticles of polypyrrole with the presence of nanotubes on their surface. Nanostructured polypyrrole powder was found to be rather amorphous even though the shape of the polypyrrole particles was induced by the crystalline and nanostructured sea urchin shaped MnO 2 powder on which they grew. In addition, neither MnO 2 nor any manganese based species were found within the produced polypyrrole powder, which ruled out the production of composite materials. cations as reaction products isolated after filtration of the reaction medium.

Effects of electrodeposition time on a manganese dioxide supercapacitor

“…19 Therefore, numerous approaches are undertaken to improve the specic capacitance of MnO 2 as an electrode, such as forming a composite electrode with conductive substrates, 20,21 making atomic defects 22,23 and modications. 24,25 Besides, among the various methods of synthesizing MnO 2 , electrochemical deposition is considered to be the simplest and relatively rapid preparation method. Moreover, it is suitable for preparing nanomaterials and MnO 2 with nanostructures greatly shortens the diffusion path of the electrolyte ions during the process of charging and discharging, which can effectively improve the specic capacitance of supercapacitors.…”

Optimizing the Polymerization Conditions of Conductive Polypyrrole

“…These unconventional properties of an organic material encourage more and more interest numerous other conducting polymers with similar properties were synthesized, such as polypyrrole (PPy), polyaniline (PANI), polythiophene (PTh), and poly (3,4-ethylenedioxythiophene) (PEDOT) etc., were discovered [3,4]. Among various conductive polymers, PPy has been extensively studied because of its extensive applications in the fields of antistatic material, rechargeable batteries, sensors, printing circuit board, stealth material, electrochromic material, drug delivery and others owing to its high electrical conductivity, redox reversibility, good environment stability, good biocompatibility, relatively easy synthesis and low toxicity [5][6][7][8].…”

“…Both can involve a template during the polymerization of pyrrole so as to obtain polypyrrole nanostructures, the products of these methods are often involved in extra steps for the removal of the template which often destroy PPy nanostructures [8,10]. The template-free emulsion polymerization methods provide a number of advantages such as the good solubility in common organic solvents and the easily of preparing a large amount of polymer.…”

Improvement of capacitive performances of symmetric carbon/carbon supercapacitors by addition of nanostructured polypyrrole powder

“…Polypyrrole and carbon materials have already been associated frequently to produce competitive composite materials for supercapacitor electrodes (see a non-exhaustive list in Table 1). Our objective was thus to benefit from a simple and efficient chemical method that was developped in our group to synthesize nanostructured PPy powders by using manganese dioxide as oxidizing agent and nanostructured template in presence of pyrrole [35]. In the work reported hereafter, the PPy powder thus obtained was used as active additive in carbon / carbon supercapacitors to improve their performances.…”