High-performance catalysts fabricated with little to no platinum for the cathode of a PEM fuel cell remain a significant challenge for commercial application due to the sluggish oxygen reduction reaction (ORR) kinetics, has been a major barrier in the development of economically enticing technology. Because of this, there are many non-precious catalysts currently being investigated to find suitable alternative that offers better integrity and stability than the standard platinum-based catalysts. A single-metal atom based organometallic catalyst, iron phthalocyanine supported on graphene (GFePc) has showed promise as a potential alternative through its performance and stability. In this work, ligand-exchanges (such as F- and NH<sub>2</sub>-) of FePc and substrate doping (such B-doping and N-doping) of graphene are explored to further enhance the performance of GFePc using spin-polarized density functional theory (DFT) calculations. Additionally, tuning the doping percentages and a combination of a ligand-exchange and substrate doping were also explored. Based on our calculations and analysis, it can be shown that Pt-free organometallic catalyst has an over potential of ~0.48 eV, which is close to the overpotential of expensive Pt catalyst.

Enhanced ORR activity of Pt-free organometallic electrocatalyst via substrate doping and/or ligand exchange

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.