Emerging heterogeneous catalysts with metal atomically dispersed on supports (tentatively termed single-atom catalysts, SACs) exhibit many appealing features in a wide variety of catalytic reactions, such as high activity and nearly 100% atom utilization. However, the synthesis of SACs currently requires not only multiple procedures but also appropriate precursors with special structures. Herein, the molten-salt assistance is presented as an effective means that enables the use of common metal oxides (such as Fe₂O₃ and Co₂O₃) and small organic molecules as precursors for the preparation of carbon-supported SACs through one-pot pyrolysis. Molten salts as templates that can be easily removed after synthesis also contribute to the formation of porous and nitrogen-doped carbon with a high specific area. More importantly, benefiting from the strong polarizing force of molten salts, the ionic bonds in oxides can be destabilized at high temperature. Subsequently, metal ions released from solid oxides are transformed into atomically dispersed active sites after being trapped by nitrogen (N) atoms on the carbon support. The as-prepared SAC with atomically dispersed Fe-N₄ sites demonstrates high activity, outstanding stability and good methanol tolerance in the oxygen reduction reaction (ORR) in both alkaline and acidic media.

具有原子分散在载体上的金属的新兴多相催化剂（暂称为单原子催化剂，SAC）在多种催化反应中表现出许多吸引人的特征，例如高活性和接近100％的原子利用率。但是，SAC的合成目前不仅需要多种步骤，而且还需要具有特殊结构的合适前体。在此，熔融盐助剂是一种有效的手段，可以使用常见的金属氧化物（如Fe ₂ O ₃和Co ₂ O ₃）和小的有机分子作为前驱物，通过一锅热解制备碳载SAC。可以在合成后轻松除去的熔融盐作为模板，也有助于形成具有高比表面积的多孔碳和氮掺杂碳。更重要的是，得益于熔融盐的强极化力，氧化物中的离子键在高温下可能不稳定。随后，从固体氧化物释放的金属离子在被碳载体上的氮（N）原子捕获后，转变为原子分散的活性位。所制备的具有原子分散的Fe-N ₄位的SAC在碱性和酸性介质中的氧还原反应（ORR）中均显示出高活性，出色的稳定性和良好的甲醇耐受性。