▎ 摘　　要

Oxygen reduction reaction is the key process that determines the performances of fuel cells and metal-air batteries. Replacing highly expensive noble metal electrocatalysts with highly active non-noble metal electrocatalysts is important for the practical application of these technologies. We have designed and synthesized a core-shell-structured catalyst consisted of silver nanowire (AgNW) core and a nitrogen-doped graphene (NG) shell that shows enhanced catalyst activity for oxygen reduction reaction in alkaline media. The newly designed structure is expected to take advantage of both one-dimensional AgNWs for fast electron transfer and two-dimensional NG for efficient oxygen adsorption/activation. The electrochemical assessments demonstrate that the prepared AgNWs@NG shows superior activity toward oxygen reduction reaction than either NG or AgNWs alone, demonstrating the synergistic effect between Ag and NG. Furthermore, the prepared catalysts show perfect (nearly 100%) four-electron (4e(-)) pathway selectivity in alkaline aqueous solution, indicating the potential substitute for Pt-based catalysts in fuel cells and metal-air batteries.