Oxygen-Tolerant Electrodes with Platinum-Loaded Covalent Triazine Frameworks for the Hydrogen Oxidation Reaction

Reducing the use of platinum (Pt) on polymer electrolyte fuel cell anodes is critical for the widespread dissemination of these energy conversion systems. Although Pt usage can be minimized by the even dispersion of isolated Pt atoms, no atomically dispersed Pt catalysts that promote hydrogen oxidation at a rate required for practical fuel cells have been reported to date. Covalent triazine frameworks with atomically dispersed Pt atoms (0.29 wt%) are described and it is demonstrated that the material has a high electrocatalytic hydrogen oxidation activity without an overpotential. Importantly, when the loading amount was increased to 2.8 wt%, the electrocatalytic hydrogen oxidation activity of the resulting electrode was comparable to that of commercial carbon supported 20 wt% Pt catalysts, and the catalytic activity for oxygen reduction was markedly reduced. Thus, Pt-modified covalent triazine frameworks selectively catalyze hydrogen oxidation, even in the presence of dissolved oxygen, which is critical for limiting cathode degradation during the start-stop cycles of fuel cells.