Shifting electrochemical oxygen reduction towards 2e–pathway to hydrogen peroxide (H2O2), instead of the traditional 4e–to water, becomes increasingly important as a green method for H2O2generation. Here, through a flexible control of oxygen reduction pathways on different transition metal single atom coordination in carbon nanotube, we discovered Fe-C-O as an efficient H2O2catalyst, with an unprecedented onset of 0.822 V versus reversible hydrogen electrode in 0.1 M KOH to deliver 0.1 mA cm−2H2O2current, and a high H2O2selectivity of above 95% in both alkaline and neutral pH. A wide range tuning of 2e–/4e–ORR pathways was achieved via different metal centers or neighboring metalloid coordination. Density functional theory calculations indicate that the Fe-C-O motifs, in a sharp contrast to the well-known Fe-C-N for 4e–, are responsible for the H2O2pathway. This iron single atom catalyst demonstrated an effective water disinfection as a representative application.
This content will become publicly available on December 1, 2023
- Award ID(s):
- 1900039
- Publication Date:
- NSF-PAR ID:
- 10352259
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Sponsoring Org:
- National Science Foundation
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