| 초록 |
Carbon materials are widely used as catalyst supports due to their high surface area, good conductivity, chemical stability, and low cost. However, immobilizing catalysts on a carbon support commonly requires high-temperature annealing for more than several hours, which induces severe aggregation of metal ions and their loose attachment to the support. Here, we propose an ultrafast method termed ‘selective microwave annealing’ (SMA) method to stabilize concentrated single atom catalytic sites on a highly reduced form of carbon host with only a few minutes of microwave irradiation. Thus, nitrogen-coordinated single atom iron sites on carbon nanotube (Fe–N4/CNT) synthesized via SMA shows unprecedented ORR activity and pH-universal durability superior to those of thermally annealed Fe–N4/CNT and expensive Pt/C catalysts. Furthermore, an aqueous Na-air battery with our Fe–N4/CNT catalyst operates as effectively as the device with Pt/C catalyst. |
