Mass production of highly efficient, durable, and inexpensive single atomic catalysts is currently the major challenge associated with the oxygen reduction reaction (ORR) for fuel cells. In this study, we develop a general strategy that uses a simple ultrasonic atomization coupling with pyrolysis and calcination process to synthesize single atomic FeNC catalysts (FeNC SACs) at large scale. The microstructure characterizations confirm that the active centers root in the single atomic Fe sites chelating to the four-fold pyridinic N atoms. The identified specific Fe active sites with the variable valence states facilitate the transfer of electrons, endowing the FeNC SACs with excellent electrochemical ORR activity. The FeNC SACs were used as cathode catalysts in a homemade Zn-air battery, giving an open-circuit voltage (OCV) of 1.43 V, which is substantially higher than that of commercial Pt/C catalysts. This study provides a simple approach to the synthesis of single atomic catalysts at large scale.

目前，与燃料电池的氧还原反应（ORR）相关的主要挑战是批量生产高效，耐用且廉价的单原子催化剂。在这项研究中，我们开发了一种通用策略，该策略使用简单的超声雾化结合热解和煅烧过程来大规模合成单原子FeNC催化剂（FeNC SAC）。微观结构表征证实，活性中心起源于与四倍吡啶N原子螯合的单原子Fe位。鉴定出的具有可变价态的特定Fe活性位点促进了电子的转移，使FeNC SAC具有出色的电化学ORR活性。FeNC SAC在自制的Zn-空气电池中用作阴极催化剂，其开路电压（OCV）为1.43 V，远高于市售Pt / C催化剂。这项研究为大规模合成单原子催化剂提供了一种简单的方法。