Silver Clusters with Adatoms as a Catalyst for the Oxygen Reduction Reaction

Developing highly active and low-cost catalysts for theoxygenreduction reaction (ORR) is critical for renewable energy devicessuch as metal-air cells and fuel cells. In this work, we reportan active ORR catalyst, Ag clusters with adatoms, which can be facilelyproduced by a pulse electrolysis method. The silver adatom on thesilver cluster can reduce the coordination number, upshift the Agd-band center, lower the ORR reaction barrier, and eventually transformthe inactive Ag into a highly active catalyst. As a result, the catalystexhibits high activity and stability, which are superior to ever-reportedsilver-based catalysts and even the commercial Pt/C catalyst.