In situ solution plasma synthesis of silver nanoparticles supported on nitrogen-doped carbons with enhanced oxygen reduction activity

Silver nanoparticles supported on nitrogen-doped carbons (Ag/NC) were in situ synthesized by a solution plasma process. In the solution plasma, Ag nanoparticles were produced via the sputtering of Ag electrode, while the NC supports were simultaneously synthesized from 2-cyanopyridine (C6H4N2). The results of the characterization show that Ag nanoparticles had good crystallinity and the NC supports possessed an amorphous structure. The oxygen reduction reaction (ORR) catalyzed on Ag/NC proceeded via the co-existence of two and four-electron pathways in alkaline solution, with the four-electron pathway being found to be more dominant. An enhanced ORR activity of Ag/NC was attributed to the synergistic effect of Ag nanoparticles and NC supports. Moreover, Ag/NC exhibited long-term durability and high resistance to methanol oxidation in comparison with the commercial Pt/C catalyst.