Heat-treatment effects on the ORR activity of Pt nanoparticles deposited on multi-walled carbon nanotubes using magnetron sputtering technique

• Published in: International journal of hydrogen energy Vol. 42; no. 9; pp. 5958 - 5970
• Main Authors: Hussain, Sajid, Erikson, Heiki, Kongi, Nadezda, Merisalu, Maido, Ritslaid, Peeter, Sammelselg, Väino, Tammeveski, Kaido
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 02.03.2017
• Subjects: Carbon nanotubes; Composite catalysts; Electrocatalysis; Magnetron sputtering; Oxygen reduction; Pt nanoparticles; Pt nanoparticles; Carbon nanotubes; Oxygen reduction; Electrocatalysis; Composite catalysts; Magnetron sputtering
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2016.11.164

Platinum nanoparticles supported on acid-treated multi-walled carbon nanotubes (Pt/MWCNT) catalysts were prepared through magnetron sputtering of Pt. The prepared Pt/MWCNT composites were annealed at different temperatures to study heat-treatment effects on the particle size, surface morphology, and the oxygen reduction reaction (ORR) activity. High-resolution scanning electron microscopy (SEM) was used to study the surface morphology of Pt/MWCNT catalysts. For surface characterization, CO oxidation and cyclic voltammetry were performed in 0.1 M KOH and 0.05 M H2SO4 solutions. The ORR activity of the electrocatalysts annealed at different temperature was studied in these solutions using the rotating disk electrode (RDE) method and the results were compared to those of the commercial Pt/C catalysts. Specific activity for oxygen reduction on Pt/MWCNT catalysts was higher than that of Pt/C, however, the mass activity was lower due to a larger Pt particle size of Pt/MWCNT catalysts. •Pt/MWCNT electrocatalysts were prepared using the magnetron sputtering technique.•Pt/MWCNT catalysts were heat-treated to change the morphology of the composites.•Oxygen reduction on the Pt/MWCNT composites was studied in acid and alkaline media.•The electrocatalytic activity for ORR was highest for the material annealed at 300 °C.•Tafel behavior of ORR was similar for Pt/MWCNT, bulk Pt and commercial Pt/C catalyst.