Peptide A4 based AuAg alloyed nanoparticle networks for electrocatalytic reduction of oxygen.

Peptide based methods create new revenues to fabricate stable, multifunctional noble metal nanomaterials under mild and green synthesis conditions. Peptide sequence A4 stabilized AuAg alloyed nanomaterials were fabricated through a facile and straightforward approach. The as-prepared alloyed nanomaterials demonstrated effective catalytic activity toward oxygen electroreduction in alkaline media. Both the metal-to-A4 ratio and Au-to-Ag ratio were optimized to enrich the electrocatalytic performance, and the sample of Au:Ag:A4 = 10:30:1 exhibited the highest activity among the series. The performance of Au:Ag:A4 = 10:30:1 is comparable with that of commercial Pt/C, within the context of onset potential, diffusion-limited current density as well as long-term stability. The as-prepared samples were characterized by UV–visible absorbance, transmission electron microscopy (TEM), as well as X-ray photoelectron microscopy (XPS). The improved activity is probably attributed to the alloying induced ensemble effects and electronic effects. This discovery may shed light on fabricating peptide based alloys as highly efficient catalysts with enhanced stability for oxygen reduction reaction (ORR). [ABSTRACT FROM AUTHOR]