Biomass-based carbon support for non-precious metal ORR catalysts

Abstract

Aim of this study is to fabricate a novel biomass-based carbon support for Fe-N-C catalysts with enlarged surface area and porosity compared to common carbon blacks to promote higher active site density and, therefore, higher volumetric activity. Strawbased activated carbon can provide a high surface area of 2016 m2/g, in comparison to raw oil-based commercial carbon blacks like Vulcan® or Black Pearls® with surface areas of 213 m2/g [5] and 1379 m2/g.

Synthesis of sustainable porous carbon support is done by pyrolysis of straw followed by KOH activation. A comparison of biomass-based activated carbon as novel support on one hand and fossil-based carbon black on other hand in Fe-N-C catalysts is given in terms of physical characterization. This includes the specific surface area and pore size distribution as well as the determination of elemental composition and functional groups by XPS and FT-IR spectroscopy. Furthermore, study of the porous morphology by TEM and SEM is shown. The synthesis of final Fe-N-C is carried out by impregnation of carbon support with iron acetate and cyanamide followed by pyrolysis at 900°C, acid leaching and a second pyrolysis.