Nanoparticles of Ag, Pt and Pt–Ag were synthesized using ultrasonic irradiation with no consecutive thermal
treatment to catalyze the oxygen reduction reaction. Metal nanoparticles are supported on carbon substrate.
The synthesized materials were characterized by XRD, TEM, and cyclic and lineal voltammetry techniques. The
kinetic formation of the metallic nanoparticles in solution was followed using UV–vis spectroscopy. The metal
particles have crystalline structure and particle size withb 10 nm in size and in the form of spherical agglomer-ates. Ag/C exhibits lower electrochemical activity and stability for the ORR compared to Pt/C and Pt –Ag/C in acid
medium. The mass and specific activity results demonstrate that the synthesized bimetallic sample exhibits 1.5
and 5 times greater electrochemical activities for the ORR compared to the commercial sample.