Excellent Oxygen Reduction Reaction Performance in Self-Assembled Amyloid-β/Platinum Nanoparticle Hybrids with Effective Platinum–Nitrogen Bond Formation

Abstract

The development of highly efficient catalysts for electrochemical oxygen reduction reactions (ORRs) is crucial for energy applications such as metal–air batteries and fuel cells. Here, we show an enhanced electrocatalytic activity of a new functional material composed of Pt nanoparticles (PtNPs) and self-assembled β-sheet peptides (βPs). The PtNP/βP hybrids, under an optimized assembly condition, display an ORR electrocatalytic activity that is higher than that of a commercially available benchmark Pt/C electrocatalyst in terms of the onset potential and reaction kinetics. Moreover, the PtNP/βP hybrids show one order of magnitude higher ORR mass activity than previously reported peptide-based ORR electrocatalysts. The superb ORR activity with high durability is derived from the well-dispersed PtNPs on βPs, where 50% of the amine groups on the side chain bound with Pt to form Pt–N bonds that function as active sites for the catalytic reaction. This work opens new avenues for efficient ORR electrocatalysts using self-assembled peptides.