How Effective Is Graphitization of Biomasses for the Carbon Stability of Pt/C ORR Catalysts?
Henrike Schmies, Nina Bengen, Julia Müller‐Hülstede, Olayinka Ahmed Ibitowa, Peter Wagner, Michael Wark
Abstract
Catalysts for the oxygen reduction reaction (ORR) in PEM fuel cells are commonly constituted of Pt-based nanoparticles and a carbon support originating from fossil resources. In order to employ a more sustainable carbon support, activated sawdust was chosen in this study. This was firstly steam-activated at 750 °C and then thermally treated at elevated temperatures up to 2800 °C and reducing conditions at 1100 °C. Various physical characterization methods were applied to systematically relate treatment parameters to surface and structural properties of the carbon material. Deposition of small Pt nanoparticles on the biochar-based supports yielded in ORR active catalysts which were analyzed by thin-film rotating disc electrode measurements. The activity and stability towards the ORR of these novel catalysts was compared to a commercial raw oil-based Pt/C and the influence of support modification on the ORR performance was discussed.