Tailoring of carbonized polypyrrole nanotubes core by different polypyrrole shells for oxygen reduction reaction selectivity modification

0504696 - ÚMCH 2020 RIV US eng J - Journal Article
Minisy, Islam M. - Gavrilov, N. - Acharya, Udit - Morávková, Zuzana - Unterweger, C. - Mičušík, M. - Filippov, Sergey K. - Kredatusová, Jana - Pašti, I. A. - Breitenbach, S. - Ciric-Marjanovic, G. - Stejskal, Jaroslav - Bober, Patrycja
Tailoring of carbonized polypyrrole nanotubes core by different polypyrrole shells for oxygen reduction reaction selectivity modification.
Journal of Colloid and Interface Science. Roč. 551, 1 September (2019), s. 184-194. ISSN 0021-9797. E-ISSN 1095-7103
R&D Projects: GA ČR(CZ) GA18-04669S; GA MŠMT(CZ) 8X17027
Institutional support: RVO:61389013
Keywords : polypyrrole * nanotubes * coating
OECD category: Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics
Impact factor: 7.489, year: 2019
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S002197971930493X?via%3Dihub

By using methyl orange template, polypyrrole nanotubes were obtained by the oxidative polymerization of pyrrole. The nanotubes were carbonized in inert atmosphere to nitrogen-enriched carbon nanotubes. These were subsequently coated with 20 wt% of polypyrrole prepared in the absence or the presence of anionic dyes (methyl orange or Acid Blue 25). The morphology of all the samples was examined by the electron microscopies, FTIR and Raman spectroscopies. Moreover, X-ray photoelectron spectroscopy and elemental analysis were used to prove the chemical structure and the successful coating process. Electron paramagnetic resonance analysis was used to calculate the spin concentrations. Significant impact of coating method is evidenced with neat polypyrrole coating providing a two-fold capacitance increase compared to uncoated nanotubes, while coating in the presence of Acid Blue 25 decreasing it slightly. With respect to oxygen reduction reaction, coatings irreversibly transformed in the first few cycles in the presence of the products of O2 reduction, presumably hydrogen peroxide, altering the oxygen reduction mechanism. This transformation allows the tailoring of the polymeric shell, over ORR active carbonaceous core, and tuning of the catalyst selectivity and optimization of materials performance for a given application – from alkaline fuel cells to hydrogen peroxide generation.
Permanent Link: http://hdl.handle.net/11104/0296287