The synthesis of new “Pt‐free” electrocatalysts (ECs) for the oxygen reduction reaction (ORR) is reported. The ECs are characterized by a hierarchical “core‐shell” morphology; the “core” is made of graphene, that is covered by a cratered, microporous carbon nitride (CN) “shell”. The latter supports nanoparticles of M1 and Sn metals (M1=Co; Ni) in “coordination nests”. The latter are holes in the CN matrix, whose walls consist of N‐ and C‐ligands. Two groups of ECs are studied: (i) “pristine” ECs; and (ii) “activated” ECs, that are obtained from the “pristine” ECs by means of a suitable activation process (A) aimed at improving the performance in the ORR. Here, the interplay existent between (i) the chemical composition, morphology, structure and A; and (ii) the ORR performance and mechanism is investigated. The resulting insights improve the fundamental understanding of this family of ECs and open the door to the devising of new preparations of “Pt‐free” ECs for the ORR, which: (i) are stabilized by a CN matrix and; (ii) exhibit an improved performance.

中文翻译：

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分层氮化碳-石墨烯基电催化剂上负载的（Co，Ni）Sn0.5纳米粒子用于氧还原反应

据报道，用于氧还原反应（ORR）的新型“无Pt ”电催化剂（ECs）的合成。EC具有分层的“核壳”形态。“核”由石墨烯制成，并被火山口，微孔氮化碳（CN）“壳”覆盖。后者在“配位嵌套”中支撑M1和Sn金属（M1 = Co; Ni）的纳米颗粒。后者是CN矩阵中的孔，其壁由N和C配体组成。研究了两组EC：（i）“原始” EC；（ii）通过适当的激活过程从“原始” EC中获得的“激活的” EC （A），旨在提高ORR中的效果。在此，（i）化学组成，形态，结构与A之间存在相互作用。（ii）研究ORR的性能和机制。由此产生的见解增进了对该EC系列的基本了解，并为ORR的“无Pt ” EC新制剂的开发打开了大门，这些措施包括：（i）由CN矩阵稳定；以及 （ii）表现出改善的性能。