Morphology Control and Electro catalytic Activity towards Oxygen Reduction of Peptide-Templated Metal Nanomaterials: A Comparison between Au and Pt

Peptide templated noble metal nanomaterials have been considered as an emerging type of nanomaterials, which can find widespread catalytic applications in a variety of organic reactions. However, their electrocatalytic properties remained largely unexplored. Herein, peptide R5 templated Au and Pt nanomaterials were fabricated and employed as catalysts for oxygen reduction reaction (ORR). By tuning the metal-to-peptide ratio, different shaped Au and Pt nanomaterials were obtained and observed by TEM measurements. With lower metal-to-peptide ratios, spherical nanoparticles were obtained for both Au and Pt, while higher metal-to-peptide ratios led to the formation of nanoribbons and/or networked nanochains. All the Au and Pt nanomaterials demonstrated good ORR activity, while R5-Au-90 and R5-Pt-90 exhibited the best performance in their own series. Morphological effects of Au and Pt nanomaterials upon ORR were established. R5-Pt-90 exhibited comparable activity with Pt/C, as manifested by the onset potential, specific activity as well as the long-term durability. The findings can shed light on rational design of peptide templated noble metal nanomaterials with desired morphology and optimized electrochemical properties as catalyst for electrochemical reactions.