Cobalt single atoms loading on carbon black for efficient hydrogen peroxide production

The production of hydrogen peroxide (H 2 O 2 ) by 2-electron oxygen reduction reaction (ORR) in acidic electrolytes is a promising alternative to the existing anthraquinone process. However, the development of cost-effective catalysts with high activity for H 2 O 2 electrosynthesis remains a great challenge. Here, we report a cobalt-nitrogen-carbon catalyst in which cobalt single atoms are supported on carbon black (Co-N-CB) for the electrosynthesis of H 2 O 2 in an acid medium. The prepared Co-N-CB shows high activity for O 2 reduction into H 2 O 2 with an average selectivity of 80.6% over a wide potential range of 0.1–0.7 V vs. RHE in 0.1 M HClO 4 electrolytes. We found that (i) the Co single atoms are the active sites of 2-electron ORR; (ii) a catalyst for efficient H 2 O 2 production by O 2 reduction should achieve a good balance between high ORR activity and H 2 O 2 selectivity. Using Co-N-CB as a cathodic catalyst, the electrochemical device could electrosynthesize H 2 O 2 directly from H 2 and O 2 with a high productivity of 291.0 mol kg cat −1 h −1 . Our work provides a flexible way to prepare affordable catalysts for efficient H 2 O 2 electrosynthesis.