Tuning the atomic configuration of Co-N-C electrocatalyst enables highly-selective H2O2 production in acidic media

The oxygen reduction reaction (ORR) is essential for both energy conversion devices and green hydrogen peroxide (H2O2) synthesis. Whereas, it remains a challenge to efficiently tune the oxygen reduction selectivity toward the target applications. Herein, we designed two kinds of Co-N-C materials with encapsulated Co nanoparticles (CoNP-N-C) and with atomically dispersed cobalt atoms strongly embedded into nitrogen-doped carbon nanotubes (CoSA-N-CNTs), and successfully realized the ORR pathway transformation from four-electron (4e−) to two-electron (2e−) for high-performance H2O2 production. This tunability is ascribed to the modification of the atomic configuration of the Co-N-C catalyst. Remarkably, when employing CoSA-N-CNTs material as a 2e− ORR catalyst, the assembled electrode exhibits a high H2O2 production rate of approximately 974 ± 25 mmol gcat−1 h−1, along with an ultra-fast organic matter degradation performance. This work provides an efficient strategy for tuning oxygen reduction selectivity via a simple structure tuning of the materials for specific applications.